Next Generation 911 (NG911) is an Internet Protocol based emergency calling system that federal rules define as secure, interoperable, built on commonly accepted standards, and able to let emergency communications centers handle every type of 911 request rather than voice alone [1]. Enhanced 911 (E911) is the circuit-switched system it replaces, in which a selective router picks the answering center by comparing the caller's information against a routing table built from a Master Street Address Guide and an ANI/ALI database, then sends the call over dedicated trunks [2]. The core differences are the transport and the routing input: NG911 carries calls as SIP sessions into an Emergency Services IP Network and chooses the destination by mapping a validated location against emergency response zone boundaries, and the location travels inside the call signaling as PIDF-LO instead of being looked up after the call arrives [1][3]. NG911 also accepts text, photos, video, and data that legacy 911 networks cannot carry [2][5]. In the United States the changeover is request-driven rather than scheduled: an originating service provider has six or twelve months, depending on its category, to meet each phase after a 911 authority sends a valid request [1].
\n","summary":"Legacy E911 hands a 911 call to a selective router that consults a stored address table to pick an answering center. NG911 carries the same call as a SIP session over an Emergency Services IP Network, chooses the destination by mapping a validated location against response zone boundaries, and can accept text, images, video, and data. US rules make the switch request-driven rather than scheduled: providers get six or twelve months to comply once a 911 authority certifies its network is ready.","publishedAt":"2026-07-20T16:31:53.296","verifiedAt":"2026-07-17T00:00:00","editorialStatus":"APPROVED","lastReviewedAt":"2026-07-17T00:00:00","nextReviewDueAt":"2026-10-17T00:00:00","templateVersion":"v2","aliases":["NG911 vs E911","What is NG911?","What is the difference between Next Generation 911 and Enhanced 911?","NG9-1-1 explained","How is NG911 different from E911?","What does Next Generation 911 mean?","NG911 definition","E911 vs NG911 for businesses","What is an ESInet?","Is NG911 replacing E911?","NG911 requirements for service providers","Next Generation 911 architecture"],"confidenceScore":92,"confidenceLabel":"High","canonicalUrl":null},"contributor":{"id":"ec39deab-44fe-48d8-9029-fefe993ab85a","slug":"answer-stack","displayName":"AnswerStack","websiteUrl":null},"contributorOrganizationProfile":{"entityId":"ec39deab-44fe-48d8-9029-fefe993ab85a","legalName":null,"description":null,"websiteUrl":null,"imageUrl":null,"slogan":null,"subtitle":null,"facts":[],"coiNote":null,"foundingDate":null,"numberOfEmployeesText":null,"contactPoint":null,"address":null,"headquartersText":null,"organizationType":null},"contributorPerson":{"slug":"answerstack-editorial-team","displayName":"AnswerStack Editorial Team"},"sections":[{"id":"6315b524-6993-4f87-a548-dd22609d2ef7","sectionKey":"what_ng911_is","sectionType":"markdown_section","heading":"What is Next Generation 911?","introMarkdown":"Next Generation 911, written NG911 or NG9-1-1, is an Internet Protocol based emergency calling system that is replacing the circuit-switched network behind 911 in the United States. Federal rules define NG911 as an IP-based system built on commonly accepted standards that is secure and interoperable, and that lets emergency communications centers handle every type of 911 request rather than voice alone [1]. Enhanced 911, shortened to E911, is the system being replaced, so the two names describe different generations of infrastructure rather than two services a caller chooses between.\n\n### What E911 does\n\nA legacy E911 call reaches an aggregation point, the selective router. The router compares the caller's location information against an internal routing table built from a Master Street Address Guide and an ANI/ALI database, identifies the public safety answering point whose service area covers that address, and sends the call down dedicated trunks to the central office serving that PSAP [2]. The call taker then queries the ALI database using the calling number to see the address and callback number [2]. Every step assumes a voice call and a telephone number tied to a fixed address.\n\n### What NG911 puts in its place\n\nNG911 carries the same call as a SIP session into an Emergency Services IP Network, which the FCC defines as an IP-based network managed or operated by a 911 authority or its agents and vendors [1]. Inside that ESInet, a group of NG911 Core Services takes over the work the selective router, the MSAG, and the ANI/ALI database used to do. A Location Validation Function checks civic addresses against a Geographic Information System database, an Emergency Call Routing Function maps a validated location inside the boundaries of emergency response zones to identify the destination PSAP, and an Emergency Services Routing Proxy delivers the call according to a Policy Routing Function's rules [3].\n\n### How far along the change is\n\nAbout 217 million calls reach 911 in the United States each year [2], and the network under them is being rebuilt jurisdiction by jurisdiction rather than on one cutover date. Forty-two states plus the District of Columbia, Guam, and Puerto Rico reported spending on NG911 programs in calendar year 2024, totaling roughly $535 million [3]. When the FCC adopted its transition rules in 2024, no fully enabled NG911 system was yet operating, though many jurisdictions had already deployed ESInets and other transitional pieces [2].","introHtml":"Next Generation 911, written NG911 or NG9-1-1, is an Internet Protocol based emergency calling system that is replacing the circuit-switched network behind 911 in the United States. Federal rules define NG911 as an IP-based system built on commonly accepted standards that is secure and interoperable, and that lets emergency communications centers handle every type of 911 request rather than voice alone [1]. Enhanced 911, shortened to E911, is the system being replaced, so the two names describe different generations of infrastructure rather than two services a caller chooses between.
\nA legacy E911 call reaches an aggregation point, the selective router. The router compares the caller's location information against an internal routing table built from a Master Street Address Guide and an ANI/ALI database, identifies the public safety answering point whose service area covers that address, and sends the call down dedicated trunks to the central office serving that PSAP [2]. The call taker then queries the ALI database using the calling number to see the address and callback number [2]. Every step assumes a voice call and a telephone number tied to a fixed address.
\nNG911 carries the same call as a SIP session into an Emergency Services IP Network, which the FCC defines as an IP-based network managed or operated by a 911 authority or its agents and vendors [1]. Inside that ESInet, a group of NG911 Core Services takes over the work the selective router, the MSAG, and the ANI/ALI database used to do. A Location Validation Function checks civic addresses against a Geographic Information System database, an Emergency Call Routing Function maps a validated location inside the boundaries of emergency response zones to identify the destination PSAP, and an Emergency Services Routing Proxy delivers the call according to a Policy Routing Function's rules [3].
\nAbout 217 million calls reach 911 in the United States each year [2], and the network under them is being rebuilt jurisdiction by jurisdiction rather than on one cutover date. Forty-two states plus the District of Columbia, Guam, and Puerto Rico reported spending on NG911 programs in calendar year 2024, totaling roughly $535 million [3]. When the FCC adopted its transition rules in 2024, no fully enabled NG911 system was yet operating, though many jurisdictions had already deployed ESInets and other transitional pieces [2].
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":10},{"id":"9f6ed1ae-15be-422d-b1ca-d86f97a44938","sectionKey":"ng911_vs_e911_table","sectionType":"table_section","heading":"How does NG911 differ from E911?","introMarkdown":"Five things change between the two architectures, and each gets its own section below.","introHtml":"Five things change between the two architectures, and each gets its own section below.
\n","outroMarkdown":"The consequences of each row differ depending on whether you buy voice service, run a phone system, or operate a 911 network.","outroHtml":"The consequences of each row differ depending on whether you buy voice service, run a phone system, or operate a 911 network.
\n","contentJson":{"rows":[{"cells":["How the call travels","TDM circuits into a selective router, then dedicated trunks to the PSAP [2]","SIP sessions into an ESInet, with gateways wherever legacy pieces remain [1][4]"]},{"cells":["How the destination is chosen","Routing table built from MSAG and ANI/ALI data, or, for wireless, the serving cell tower [2][9]","ECRF maps a validated location onto response zone boundaries [3]"]},{"cells":["How location reaches the call taker","PSAP queries an ALI database using the calling number after the call arrives [2]","Location rides in the signaling as PIDF-LO, validated in advance by an LVF [1][10]"]},{"cells":["What a caller can send","Voice, plus text-to-911 where separately deployed [2][5]","Voice, text, photos, video, and data [2][5]"]},{"cells":["Who operates and pays for what","Selective routers and trunks built by incumbent carriers, paid through state tariffs [2]","911 authorities own the ESInet and core services; providers pay to reach the delivery point [1]"]}],"columns":["What changes","Legacy E911","NG911"]},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":20},{"id":"e67d3e2e-f28a-4b8a-950d-38ec6fe9c422","sectionKey":"routing_differences","sectionType":"markdown_section","heading":"How does NG911 decide which PSAP receives a call?","introMarkdown":"Routing in NG911 is geospatial rather than tabular. The Emergency Call Routing Function takes a validated caller location and determines the destination PSAP by mapping that location inside the boundaries of emergency response zones, after which an Emergency Services Routing Proxy delivers the call according to the policy rules a 911 authority has configured [3]. Legacy E911 does the same job with a lookup table inside the selective router, populated from MSAG and ANI/ALI data, so the decision is only as good as the address record attached to the telephone number [2].\n\nThe difference is most visible on wireless calls. Wireless 911 calls have historically been routed on the location of the cell tower handling the call, so a call placed near a county line can land at the wrong PSAP because the tower sits in a different jurisdiction, and the receiving center then has to transfer it [9]. The FCC treated part of that problem separately in 2024 by requiring wireless providers to use location-based routing on their IP networks [9]. NG911 applies the same logic to every call type by making mapped geography, rather than a stored table, the routing input.\n\nFor a business, the consequence is that address accuracy stops being a billing detail. Under the NENA i3 architecture, once transition is complete the selective routers and existing ALI systems are decommissioned and calls route through the ECRF over SIP [4], so an address that fails GIS validation has nothing to fall back on. Reconciling every site, floor, and suite record your provider holds against the authoritative address data for that jurisdiction is work best done before your carrier's Phase 2 deadline.","introHtml":"Routing in NG911 is geospatial rather than tabular. The Emergency Call Routing Function takes a validated caller location and determines the destination PSAP by mapping that location inside the boundaries of emergency response zones, after which an Emergency Services Routing Proxy delivers the call according to the policy rules a 911 authority has configured [3]. Legacy E911 does the same job with a lookup table inside the selective router, populated from MSAG and ANI/ALI data, so the decision is only as good as the address record attached to the telephone number [2].
\nThe difference is most visible on wireless calls. Wireless 911 calls have historically been routed on the location of the cell tower handling the call, so a call placed near a county line can land at the wrong PSAP because the tower sits in a different jurisdiction, and the receiving center then has to transfer it [9]. The FCC treated part of that problem separately in 2024 by requiring wireless providers to use location-based routing on their IP networks [9]. NG911 applies the same logic to every call type by making mapped geography, rather than a stored table, the routing input.
\nFor a business, the consequence is that address accuracy stops being a billing detail. Under the NENA i3 architecture, once transition is complete the selective routers and existing ALI systems are decommissioned and calls route through the ECRF over SIP [4], so an address that fails GIS validation has nothing to fall back on. Reconciling every site, floor, and suite record your provider holds against the authoritative address data for that jurisdiction is work best done before your carrier's Phase 2 deadline.
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":30},{"id":"3dfa9b8a-ebe3-4db9-aec7-eebdd6264964","sectionKey":"location_handling","sectionType":"markdown_section","heading":"How does NG911 handle caller location?","introMarkdown":"NG911 moves location into the call itself. Phase 2 of the FCC's transition framework requires an originating service provider to deliver 911 traffic in SIP with location embedded in the signaling using Presence Information Data Format Location Object, known as PIDF-LO, or its functional equivalent, and to run a Location Information Server for verifying customer location records [1]. That replaces the legacy pattern, where the PSAP pulls an address from an ALI database once the call has landed [2].\n\nThe underlying method is an IETF best current practice. Emergency calls are marked with a service URN, location travels between SIP entities in either civic or geodetic form using the extension defined in RFC 6442, and the call is routed on that location through the Location-to-Service Translation protocol [10]. Providers already move location this way in production, passing it through PIDF-LO headers for customers whose phones move around a network rather than sitting at one fixed jack [13][10].\n\nE911 has its own location obligations, and they remain in force. Wireless providers still owe either dispatchable location or horizontal accuracy within 50 meters for a rising share of calls, plus vertical location within 3 meters of the handset for 80 percent of calls from z-axis capable devices [6]. Interconnected VoIP providers still owe automated dispatchable location for fixed service, and for nomadic service either a registered location the customer can update, alternative location information, or routing to a national emergency call center [7]. Multi-line telephone systems still owe direct 911 dialing and dispatchable location under Kari's Law and section 506 of RAY BAUM'S Act [8]. NG911 changes how those obligations are met, not whether they apply.","introHtml":"NG911 moves location into the call itself. Phase 2 of the FCC's transition framework requires an originating service provider to deliver 911 traffic in SIP with location embedded in the signaling using Presence Information Data Format Location Object, known as PIDF-LO, or its functional equivalent, and to run a Location Information Server for verifying customer location records [1]. That replaces the legacy pattern, where the PSAP pulls an address from an ALI database once the call has landed [2].
\nThe underlying method is an IETF best current practice. Emergency calls are marked with a service URN, location travels between SIP entities in either civic or geodetic form using the extension defined in RFC 6442, and the call is routed on that location through the Location-to-Service Translation protocol [10]. Providers already move location this way in production, passing it through PIDF-LO headers for customers whose phones move around a network rather than sitting at one fixed jack [13][10].
\nE911 has its own location obligations, and they remain in force. Wireless providers still owe either dispatchable location or horizontal accuracy within 50 meters for a rising share of calls, plus vertical location within 3 meters of the handset for 80 percent of calls from z-axis capable devices [6]. Interconnected VoIP providers still owe automated dispatchable location for fixed service, and for nomadic service either a registered location the customer can update, alternative location information, or routing to a national emergency call center [7]. Multi-line telephone systems still owe direct 911 dialing and dispatchable location under Kari's Law and section 506 of RAY BAUM'S Act [8]. NG911 changes how those obligations are met, not whether they apply.
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":40},{"id":"80d9095c-7abf-469a-b651-e218cde94f7d","sectionKey":"media_and_data","sectionType":"markdown_section","heading":"What can NG911 carry that E911 cannot?","introMarkdown":"NG911 accepts text, photos, video, and data alongside voice. The FCC describes the end state as one in which the circuit-switched architecture of legacy 911 is entirely replaced by IP technologies providing all of the same functions plus new ones, including transmission of text, photos, videos, and data to PSAPs by people seeking help [2][3]. Legacy 911 networks were built narrowband and circuit switched, carrying voice and very limited data, which is why emergency text, images, video for American Sign Language users, and telematics feeds were all awkward to support [5].\n\nThe building block that makes the difference is the ESInet itself. NENA describes ESInets as engineered, managed, packet-switched networks intended to be multi-purpose, supporting public safety communications beyond 911 alone, and designed as a network of networks spanning local through national authorities [5]. Once emergency traffic sits on a general-purpose IP network, adding a media type becomes a software question instead of a new physical circuit.\n\nTwo caveats matter for planning. Capability in the network does not mean capability at the answering position, because a PSAP still needs call handling equipment and procedures that can act on a video stream. And text-to-911 already exists outside NG911 as a separately mandated capability with its own FCC readiness registry [2], so a jurisdiction advertising text-to-911 is not necessarily running NG911.","introHtml":"NG911 accepts text, photos, video, and data alongside voice. The FCC describes the end state as one in which the circuit-switched architecture of legacy 911 is entirely replaced by IP technologies providing all of the same functions plus new ones, including transmission of text, photos, videos, and data to PSAPs by people seeking help [2][3]. Legacy 911 networks were built narrowband and circuit switched, carrying voice and very limited data, which is why emergency text, images, video for American Sign Language users, and telematics feeds were all awkward to support [5].
\nThe building block that makes the difference is the ESInet itself. NENA describes ESInets as engineered, managed, packet-switched networks intended to be multi-purpose, supporting public safety communications beyond 911 alone, and designed as a network of networks spanning local through national authorities [5]. Once emergency traffic sits on a general-purpose IP network, adding a media type becomes a software question instead of a new physical circuit.
\nTwo caveats matter for planning. Capability in the network does not mean capability at the answering position, because a PSAP still needs call handling equipment and procedures that can act on a video stream. And text-to-911 already exists outside NG911 as a separately mandated capability with its own FCC readiness registry [2], so a jurisdiction advertising text-to-911 is not necessarily running NG911.
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":50},{"id":"811372a0-71b6-4d3e-bda6-8461883ff3dd","sectionKey":"reliability_and_interoperability","sectionType":"markdown_section","heading":"How does NG911 change reliability and interoperability?","introMarkdown":"The failure modes change, so the rules changed with them. In July 2026 the FCC adopted a Second Report and Order, effective August 10, 2026, redefining which companies count as covered 911 service providers in an IP environment: operators of ESInets, NG911 Core Services providers, and providers of real-time location services, major IP transport, traffic aggregation, and the gateways converting between legacy and IP formats [3].\n\nLegacy and IP networks deal with single points of failure by different strategies. A legacy 911 network fixes the circuits and switches a call will traverse at setup, so a fault anywhere along that path can drop the transmission, and the standard mitigation is at least two physically separated sets of circuits and switches [3]. IP-based NG911 architecture is geographically distributed and load balanced, with automatic reroutes to backup equipment when hardware, software, or a database fails, so the FCC's benchmarks focus on physical diversity, operational integrity, and network monitoring suited to IP systems [3].\n\nInteroperability received a formal definition for the first time. The FCC defines it as the capability of NG911 systems, networks, and services to exchange 911 voice, text, data, and multimedia between jurisdictions, PSAPs, and service providers in real time without proprietary interfaces [3]. The Commission stopped short of a performance benchmark, instead requiring NGCS and ESInet providers to file a one-time report describing what they have done to enable interstate interoperability, and replacing annual reliability certifications with a one-time filing updated only on material change after an 18-month transition [3].","introHtml":"The failure modes change, so the rules changed with them. In July 2026 the FCC adopted a Second Report and Order, effective August 10, 2026, redefining which companies count as covered 911 service providers in an IP environment: operators of ESInets, NG911 Core Services providers, and providers of real-time location services, major IP transport, traffic aggregation, and the gateways converting between legacy and IP formats [3].
\nLegacy and IP networks deal with single points of failure by different strategies. A legacy 911 network fixes the circuits and switches a call will traverse at setup, so a fault anywhere along that path can drop the transmission, and the standard mitigation is at least two physically separated sets of circuits and switches [3]. IP-based NG911 architecture is geographically distributed and load balanced, with automatic reroutes to backup equipment when hardware, software, or a database fails, so the FCC's benchmarks focus on physical diversity, operational integrity, and network monitoring suited to IP systems [3].
\nInteroperability received a formal definition for the first time. The FCC defines it as the capability of NG911 systems, networks, and services to exchange 911 voice, text, data, and multimedia between jurisdictions, PSAPs, and service providers in real time without proprietary interfaces [3]. The Commission stopped short of a performance benchmark, instead requiring NGCS and ESInet providers to file a one-time report describing what they have done to enable interstate interoperability, and replacing annual reliability certifications with a one-time filing updated only on material change after an 18-month transition [3].
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":60},{"id":"cd8e6834-2173-429e-80b7-e98a91d49419","sectionKey":"who_does_what_when","sectionType":"markdown_section","heading":"Who has to do what, and by when?","introMarkdown":"There is no single national NG911 deadline. The FCC's framework is request-driven, so the clock starts when a 911 authority sends an originating service provider a valid Phase 1 or Phase 2 request, and the authority may only send that request after certifying that it has placed into operation the infrastructure needed to receive 911 traffic in the requested IP format and pass it to its PSAPs [1].\n\nPhase 1 obliges the provider to deliver all 911 traffic in the IP-based SIP format the authority asked for, to send it to the NG911 Delivery Points the authority designated, and to complete connectivity testing [1]. Phase 2 adds conformance with the commonly accepted NG911 standards the authority identifies, location embedded in the signaling as PIDF-LO or its functional equivalent, and a Location Information Server in operation for verifying customer location records [1].\n\nThe deadlines run from the request rather than from a calendar date. Non-rural wireline providers, nationwide CMRS providers, covered text providers, and interconnected VoIP providers get six months for each phase, while rural incumbent local exchange carriers, non-nationwide CMRS providers, and internet-based TRS providers get 12 months [1].\n\nCost responsibility is split in the rules themselves. Originating service providers pay to transmit traffic to the delivery point, to deliver it in the required SIP format including conversion through a Legacy Network Gateway, and to obtain and deliver location and routing information. They are not responsible for furnishing, maintaining, or upgrading delivery points, ESInets, core services networks, or PSAPs [1]. If you buy voice service, the useful question for your provider is which jurisdictions covering your sites have issued valid requests, and which phase the clock is running on.","introHtml":"There is no single national NG911 deadline. The FCC's framework is request-driven, so the clock starts when a 911 authority sends an originating service provider a valid Phase 1 or Phase 2 request, and the authority may only send that request after certifying that it has placed into operation the infrastructure needed to receive 911 traffic in the requested IP format and pass it to its PSAPs [1].
\nPhase 1 obliges the provider to deliver all 911 traffic in the IP-based SIP format the authority asked for, to send it to the NG911 Delivery Points the authority designated, and to complete connectivity testing [1]. Phase 2 adds conformance with the commonly accepted NG911 standards the authority identifies, location embedded in the signaling as PIDF-LO or its functional equivalent, and a Location Information Server in operation for verifying customer location records [1].
\nThe deadlines run from the request rather than from a calendar date. Non-rural wireline providers, nationwide CMRS providers, covered text providers, and interconnected VoIP providers get six months for each phase, while rural incumbent local exchange carriers, non-nationwide CMRS providers, and internet-based TRS providers get 12 months [1].
\nCost responsibility is split in the rules themselves. Originating service providers pay to transmit traffic to the delivery point, to deliver it in the required SIP format including conversion through a Legacy Network Gateway, and to obtain and deliver location and routing information. They are not responsible for furnishing, maintaining, or upgrading delivery points, ESInets, core services networks, or PSAPs [1]. If you buy voice service, the useful question for your provider is which jurisdictions covering your sites have issued valid requests, and which phase the clock is running on.
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":70},{"id":"b7fba625-a8f4-4b2e-b931-a4e77a32212e","sectionKey":"contributor_perspective","sectionType":"markdown_section","heading":"How this answer was researched","introMarkdown":"This answer was assembled from primary regulatory and standards documents rather than vendor material. The definitions, phase requirements, deadlines, and cost allocation come from 47 CFR part 9 subpart J as in force today. The architectural descriptions come from the FCC's 2024 NG911 transition Report and Order and its July 2026 Second Report and Order on NG911 reliability, both read in the Federal Register text, plus the ANSI-reviewed NENA i3 standard, with location handling cross-checked against IETF RFC 6881. Anything that changes over time is attributed to a dated source below.\n\nPractitioners who run PSAPs, operate ESInets or NG911 core services, or manage originating service provider compliance are invited to submit corrections and field detail, particularly on how transitional deployments behave in practice.","introHtml":"This answer was assembled from primary regulatory and standards documents rather than vendor material. The definitions, phase requirements, deadlines, and cost allocation come from 47 CFR part 9 subpart J as in force today. The architectural descriptions come from the FCC's 2024 NG911 transition Report and Order and its July 2026 Second Report and Order on NG911 reliability, both read in the Federal Register text, plus the ANSI-reviewed NENA i3 standard, with location handling cross-checked against IETF RFC 6881. Anything that changes over time is attributed to a dated source below.
\nPractitioners who run PSAPs, operate ESInets or NG911 core services, or manage originating service provider compliance are invited to submit corrections and field detail, particularly on how transitional deployments behave in practice.
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":"This answer was written and reviewed by the AnswerStack Editorial Team, which has no commercial stake in the products, companies, or methods discussed. Every claim is cited inline and verified on the dates shown.","noteHtml":"This answer was written and reviewed by the AnswerStack Editorial Team, which has no commercial stake in the products, companies, or methods discussed. Every claim is cited inline and verified on the dates shown.
\n","sortOrder":80},{"id":"89abd350-f805-447d-aea9-a901f6e4a55d","sectionKey":"what_ng911_is_not","sectionType":"markdown_section","heading":"What NG911 is not, and what to watch","introMarkdown":"Several common misreadings are worth clearing up first.\n\n### It is not a different number to dial\n\nCallers still dial 911. NG911 changes the network behind the number, and NENA notes the concept is international in scope and designed to support the other emergency access codes used worldwide, because the underlying processes are the same whatever digits a caller presses [5].\n\n### It is not the same subject as wireless location accuracy\n\nE911 indoor location rules and NG911 are separate tracks that often get merged. The 50 meter horizontal and 3 meter vertical standards apply to CMRS providers under the E911 rules whether or not a jurisdiction has built an ESInet [6]. NG911 changes how location is carried and used for routing, not how accurate a handset's position estimate is.\n\n### It is not a finished product in most places\n\nTransitional NG911 networks blend legacy and IP components, so many live deployments still carry selective routers, ANI/ALI, and translation gateways inside the call path while ESInets and core services are being stood up [3]. NASNA scores state progress across three separate domains, covering the 911 network, originating service providers, and PSAPs, so a state can be well advanced in one domain while lagging in another [12].\n\n### What to watch\n\nCompliance dates for several of the new reliability benchmarks were not set by the July 2026 order and will be announced in a later Federal Register document, so the effective date and the compliance date differ [3]. The further notice attached to that order asks whether multi-party interstate interoperability testing should be required, with comments due August 10, 2026 and replies due September 8, 2026 [3]. On the enterprise side, dispatchable location for a mobile workforce depends on tooling inside your own systems: Microsoft ties dynamic emergency calling in Teams to validated addresses carrying geo codes that are mapped to network identifiers, which works only while someone keeps that map current [11].","introHtml":"Several common misreadings are worth clearing up first.
\nCallers still dial 911. NG911 changes the network behind the number, and NENA notes the concept is international in scope and designed to support the other emergency access codes used worldwide, because the underlying processes are the same whatever digits a caller presses [5].
\nE911 indoor location rules and NG911 are separate tracks that often get merged. The 50 meter horizontal and 3 meter vertical standards apply to CMRS providers under the E911 rules whether or not a jurisdiction has built an ESInet [6]. NG911 changes how location is carried and used for routing, not how accurate a handset's position estimate is.
\nTransitional NG911 networks blend legacy and IP components, so many live deployments still carry selective routers, ANI/ALI, and translation gateways inside the call path while ESInets and core services are being stood up [3]. NASNA scores state progress across three separate domains, covering the 911 network, originating service providers, and PSAPs, so a state can be well advanced in one domain while lagging in another [12].
\nCompliance dates for several of the new reliability benchmarks were not set by the July 2026 order and will be announced in a later Federal Register document, so the effective date and the compliance date differ [3]. The further notice attached to that order asks whether multi-party interstate interoperability testing should be required, with comments due August 10, 2026 and replies due September 8, 2026 [3]. On the enterprise side, dispatchable location for a mobile workforce depends on tooling inside your own systems: Microsoft ties dynamic emergency calling in Teams to validated addresses carrying geo codes that are mapped to network identifiers, which works only while someone keeps that map current [11].
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":90}],"citations":[{"title":"47 CFR Part 9, Subpart J: Next Generation 911","url":"https://www.ecfr.gov/current/title-47/chapter-I/subchapter-A/part-9/subpart-J","excerpt":"Next Generation 911 (NG911). An Internet Protocol-based system that (1) Ensures interoperability; (2) Is secure; (3) Employs commonly accepted standards; (4) Enables emergency communications centers to receive, process, and analyze all types of 911 requests for emergency assistance.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"Regulatory definition of NG911, ESInet, LVF, LIS and SIP; Phase 1 and Phase 2 requirements including PIDF-LO and NG911 Delivery Points; six and twelve month implementation deadlines; valid request certifications; cost responsibilities; modification by mutual agreement with 30 day notification.","domain":"ecfr.gov","publisherName":"Electronic Code of Federal Regulations (National Archives / GPO)"},{"title":"Facilitating Implementation of Next Generation 911 Services (NG911); Location-Based Routing for Wireless 911 Calls (Report and Order, 89 FR 78066)","url":"https://www.federalregister.gov/documents/2024/09/24/2024-18603/facilitating-implementation-of-next-generation-911-services-ng911-location-based-routing-for","excerpt":"With the transition to NG911, the circuit-switched architecture of legacy 911 will eventually be entirely replaced by IP-based technologies and applications that provide all of the same functions as the legacy 911 system, as well as new capabilities.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"Legacy E911 architecture with selective router, MSAG and ANI/ALI lookup, dedicated trunks and PSAP ALI query; over 217 million 911 calls per year; NG911 end state supporting text, photos, videos and data; statement that no fully enabled NG911 systems were yet operating as of 2024; existence of the F","domain":"federalregister.gov","publisherName":"Federal Communications Commission, via Federal Register"},{"title":"Facilitating Implementation of Next Generation 911 Services (NG911); Improving 911 Reliability (Second Report and Order, 91 FR 42794)","url":"https://www.federalregister.gov/documents/2026/07/10/2026-13998/facilitating-implementation-of-next-generation-911-services-ng911-improving-911-reliability","excerpt":"The ESRP is a routing engine that queries the ECRF and routes the traffic to the geographically appropriate PSAP in accordance with the PRF, which is the rule set that decides how traffic should be routed based on predetermined policies.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"NGCS functional elements (LVF, ECRF, ESRP, PRF) replacing selective router, ANI/ALI and MSAG functions; effective date August 10, 2026; expanded covered 911 service provider definition; physical diversity contrast between legacy and IP networks; adopted NG911 interoperability definition; one-time in","domain":"federalregister.gov","publisherName":"Federal Communications Commission, via Federal Register"},{"title":"NENA i3 Standard for Next Generation 9-1-1 (NENA-STA-010.3e-2021)","url":"https://cdn.ymaws.com/www.nena.org/resource/resmgr/standards/NENA-STA-010.3e-2021_i3_Stan.pdf","excerpt":"At that point, SRs and existing ALI systems are decommissioned and all 9-1-1 calls are routed using the Emergency Call Routing Function (ECRF) and arrive at the ESInet/NGCS via Session Initiation Protocol (SIP).","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"i3 architecture and functional elements; ESInet as an IP inter-network shared by public safety agencies; use of gateways for non-IP originating networks and legacy PSAPs; end state in which selective routers and existing ALI systems are decommissioned and calls route via the ECRF over SIP.","domain":"cdn.ymaws.com","publisherName":"National Emergency Number Association (NENA)"},{"title":"What is NG9-1-1?","url":"https://cdn.ymaws.com/www.nena.org/resource/resmgr/ng9-1-1_project/whatisng911.pdf","excerpt":"Next Generation 9-1-1 (NG9-1-1) networks replace the existing narrowband, circuit switched 9-1-1 networks which carry only voice and very limited data.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"Limits of narrowband circuit-switched 911 for text, images, video and telematics or building plan data; ESInet as an engineered, managed, multi-purpose packet network arranged as a network of networks; NG911 designed to support emergency access codes used internationally.","domain":"cdn.ymaws.com","publisherName":"National Emergency Number Association (NENA)"},{"title":"47 CFR 9.10: 911 Service (wireless E911 Phase I and Phase II, indoor location accuracy)","url":"https://www.ecfr.gov/current/title-47/section-9.10","excerpt":"Within 3 meters above or below (plus or minus 3 meters) the handset for 80% of wireless E911 calls made from the z-axis capable device.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"Phase I and Phase II enhanced 911 obligations for CMRS providers; horizontal requirement of dispatchable location or x/y within 50 meters on a rising percentage schedule; z-axis metric of plus or minus 3 meters for 80 percent of calls from z-axis capable devices.","domain":"ecfr.gov","publisherName":"Electronic Code of Federal Regulations (National Archives / GPO)"},{"title":"47 CFR 9.11: E911 Service (interconnected VoIP)","url":"https://www.ecfr.gov/current/title-47/section-9.11","excerpt":"Providers of fixed interconnected VoIP services must provide automated dispatchable location with each 911 call.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"Interconnected VoIP E911 obligations: automated dispatchable location for fixed service; registered location, alternative location information, or national emergency call center routing for non-fixed service; delivery of location through the ALI database.","domain":"ecfr.gov","publisherName":"Electronic Code of Federal Regulations (National Archives / GPO)"},{"title":"47 CFR 9.16: General obligations, direct 911 dialing, notification, and dispatchable location","url":"https://www.ecfr.gov/current/title-47/section-9.16","excerpt":"a user may directly initiate a call to 911 from any station equipped with dialing facilities, without dialing any additional digit, code, prefix, or post-fix, including any trunk-access code such as the digit 9","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"Multi-line telephone system obligations under Kari's Law and section 506 of RAY BAUM'S Act: direct 911 dialing without a trunk access digit, on-site MLTS notification, and dispatchable location for fixed, on-premises non-fixed, and off-premises devices.","domain":"ecfr.gov","publisherName":"Electronic Code of Federal Regulations (National Archives / GPO)"},{"title":"Location-Based Routing for Wireless 911 Calls (Report and Order, 89 FR 18488)","url":"https://www.federalregister.gov/documents/2024/03/13/2024-03157/location-based-routing-for-wireless-911-calls","excerpt":"Wireless 911 calls have historically been routed to PSAPs based on the location of the cell tower that handles the call. Sometimes, however, the 911 call is routed to the wrong PSAP because the cell tower is not in the same jurisdiction as the 911 caller.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"Historic routing of wireless 911 calls on cell tower location; misrouting near jurisdictional borders and the resulting PSAP transfers; six month deadline for nationwide providers and 24 months for non-nationwide providers on voice, and 24 months for real-time text.","domain":"federalregister.gov","publisherName":"Federal Communications Commission, via Federal Register"},{"title":"RFC 6881: Best Current Practice for Communications Services in Support of Emergency Calling","url":"https://www.rfc-editor.org/rfc/rfc6881.html","excerpt":"The call is routed based on location using the Location-to-Service Translation (LoST) protocol, which maps a location to a set of PSAP URIs.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"Service URN marking of emergency calls; conveyance of civic or geodetic location between SIP entities using the RFC 6442 extension; routing on location via the Location-to-Service Translation (LoST) protocol.","domain":"rfc-editor.org","publisherName":"Internet Engineering Task Force (IETF)"},{"title":"Plan and manage emergency calling - Microsoft Teams","url":"https://learn.microsoft.com/en-us/microsoftteams/what-are-emergency-locations-addresses-and-call-routing","excerpt":"To assign an emergency location to a network identifier for dynamic emergency calling, the emergency address must contain an appropriate geo code.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"Enterprise dispatchable location practice: validated emergency addresses, geo codes required for assigning a location to a network identifier, and dynamic emergency calling based on the current location of the Teams client.","domain":"learn.microsoft.com","publisherName":"Microsoft Learn"},{"title":"NG911 Status","url":"https://www.nasna911.org/ng911-status","excerpt":"The 9-1-1 Network (ESInet/NGCS), Originating Service Providers (OSPs), and Public Safety Answering Points (PSAPs), each worth 0 to 10 points.","quoteText":null,"sourceRole":"INDEPENDENT","verifiedAt":"2026-07-17T00:00:00","supportsText":"State-by-state NG911 progress is scored across three separate domains: the 911 network (ESInet and NGCS), originating service providers, and PSAPs, each rated on a 0 to 10 scale.","domain":"nasna911.org","publisherName":"National Association of State 911 Administrators (NASNA)"},{"title":"How to Store Your 911 Location Data","url":"https://www.atlantech.net/blog/store-911-location-data-pidf-lo","excerpt":"This location information is then passed through to our network via PIDF-LO headers, which are special data packets that carry location information.","quoteText":null,"sourceRole":"SUPPORTING","verifiedAt":"2026-07-17T00:00:00","supportsText":"Operator-side illustration that carriers receive customer location through PIDF-LO headers, and that the dynamic PIDF-LO method suits environments where phones move rather than sitting at a fixed jack. Corroborated for the underlying protocol behavior by [10] and for the regulatory requirement by [1","domain":"atlantech.net","publisherName":"Atlantech Online"}],"revisions":[],"relatedAnswers":[{"id":"15ad4570-a86c-44b3-9049-dbaeab431c77","slug":"can-i-dial-911-from-a-voip-phone","question":"Can I dial 911 from a VoIP phone?","publishedAt":"2026-07-20T16:37:02.316","confidenceScore":93,"confidenceLabel":"High","industry":{"id":"ff619d7c-d7d7-485e-a05a-53fba07f33ed","slug":"telecommunications","label":"Telecommunications","description":"Business voice, fiber, UCaaS, and network services"},"topic":{"slug":"emergency-calling","label":"Emergency Calling","description":"911, E911, and NG911 for VoIP and SIP: registration, location accuracy, and call routing.","schemaKind":null},"contributor":{"id":"ec39deab-44fe-48d8-9029-fefe993ab85a","slug":"answer-stack","displayName":"AnswerStack","websiteUrl":null},"snippet":"United States rules treat 911 as a mandatory feature of interconnected VoIP rather than an add-on. The real variable is location. A fixed line reports a street address the provider registered, while a softphone or a business handset depends on whatever address the platform can detect or an administrator last entered. Calling apps that never touch the public phone network sit outside the rules entirely.","url":"/q/can-i-dial-911-from-a-voip-phone"},{"id":"b03c7fc2-b75b-407b-94c2-28d16792a61d","slug":"how-do-i-register-a-voip-phone-for-911","question":"How do I register a VoIP phone for 911?","publishedAt":"2026-07-20T16:31:58.611","confidenceScore":92,"confidenceLabel":"High","industry":{"id":"ff619d7c-d7d7-485e-a05a-53fba07f33ed","slug":"telecommunications","label":"Telecommunications","description":"Business voice, fiber, UCaaS, and network services"},"topic":{"slug":"emergency-calling","label":"Emergency Calling","description":"911, E911, and NG911 for VoIP and SIP: registration, location accuracy, and call routing.","schemaKind":null},"contributor":{"id":"ec39deab-44fe-48d8-9029-fefe993ab85a","slug":"answer-stack","displayName":"AnswerStack","websiteUrl":null},"snippet":"Registering a VoIP phone for 911 has five parts: find out whether you or an administrator controls the record, enter a validated street address, attach it to the right line and device, add dynamic location for anything portable, and confirm the result with a 933 test call. Fixed desk phones can run on a static address, while laptops and mobile apps need location derived from Wi-Fi, subnet, or switch data at call time.","url":"/q/how-do-i-register-a-voip-phone-for-911"},{"id":"eec6f088-b596-4007-a107-81939f09ee74","slug":"what-is-a-psap-public-safety-answering-point","question":"What is a PSAP (Public Safety Answering Point)?","publishedAt":"2026-07-20T16:31:56.115","confidenceScore":93,"confidenceLabel":"High","industry":{"id":"ff619d7c-d7d7-485e-a05a-53fba07f33ed","slug":"telecommunications","label":"Telecommunications","description":"Business voice, fiber, UCaaS, and network services"},"topic":{"slug":"emergency-calling","label":"Emergency Calling","description":"911, E911, and NG911 for VoIP and SIP: registration, location accuracy, and call routing.","schemaKind":null},"contributor":{"id":"ec39deab-44fe-48d8-9029-fefe993ab85a","slug":"answer-stack","displayName":"AnswerStack","websiteUrl":null},"snippet":"A PSAP is the designated 911 answering center that sits between the phone network and emergency responders. This answer covers the regulatory definition, the difference between primary, secondary, and backup answering points, how a call reaches the right center under legacy E911 and Next Generation 911, and the practical limits of what any single PSAP can do.","url":"/q/what-is-a-psap-public-safety-answering-point"},{"id":"dc46b870-84ce-4ca3-97d2-5d91dd4818de","slug":"what-is-enhanced-911-e911","question":"What is Enhanced 911 (E911)?","publishedAt":"2026-07-20T16:31:50.28","confidenceScore":94,"confidenceLabel":"High","industry":{"id":"ff619d7c-d7d7-485e-a05a-53fba07f33ed","slug":"telecommunications","label":"Telecommunications","description":"Business voice, fiber, UCaaS, and network services"},"topic":{"slug":"emergency-calling","label":"Emergency Calling","description":"911, E911, and NG911 for VoIP and SIP: registration, location accuracy, and call routing.","schemaKind":null},"contributor":{"id":"ec39deab-44fe-48d8-9029-fefe993ab85a","slug":"answer-stack","displayName":"AnswerStack","websiteUrl":null},"snippet":"E911 adds two things to a plain 911 call: a callback number and a location the dispatcher can act on. It began as a wireline and wireless capability and is now a compliance obligation for VoIP platforms and business phone systems, with dispatchable location, on-site notification, and direct 911 dialing written into FCC rules. Next Generation 911 is gradually replacing the selective router and location database design underneath it.","url":"/q/what-is-enhanced-911-e911"}],"contributorStats":{"verifiedAnswers":224,"openDisputes":0},"schemaJson":{"@context":"https://schema.org","@type":"Question","name":"What is Next Generation 911 (NG911), and how is it different from E911?","text":"What is Next Generation 911 (NG911), and how is it different from E911?","url":"https://www.answerstack.io/q/what-is-next-generation-911-ng911-and-how-is-it-different-from-e911","answerCount":1,"datePublished":"2026-07-20T16:31:53.296","author":{"@type":"Person","name":"AnswerStack Editorial Team","worksFor":{"@type":"Organization","name":"AnswerStack"},"url":"https://www.answerstack.io/contributors/answer-stack"},"about":[{"@type":"Thing","name":"Emergency Calling"},{"@type":"Thing","name":"Telecommunications"}],"acceptedAnswer":{"@type":"Answer","text":"Next Generation 911 (NG911) is an Internet Protocol based emergency calling system that federal rules define as secure, interoperable, built on commonly accepted standards, and able to let emergency communications centers handle every type of 911 request rather than voice alone [1]. Enhanced 911 (E911) is the circuit-switched system it replaces, in which a selective router picks the answering center by comparing the caller's information against a routing table built from a Master Street Address Guide and an ANI/ALI database, then sends the call over dedicated trunks [2]. The core differences are the transport and the routing input: NG911 carries calls as SIP sessions into an Emergency Services IP Network and chooses the destination by mapping a validated location against emergency response zone boundaries, and the location travels inside the call signaling as PIDF-LO instead of being looked up after the call arrives [1][3]. NG911 also accepts text, photos, video, and data that legacy 911 networks cannot carry [2][5]. In the United States the changeover is request-driven rather than scheduled: an originating service provider has six or twelve months, depending on its category, to meet each phase after a 911 authority sends a valid request [1].","url":"https://www.answerstack.io/q/what-is-next-generation-911-ng911-and-how-is-it-different-from-e911","upvoteCount":0,"datePublished":"2026-07-20T16:31:53.296","dateModified":"2026-07-17T00:00:00","author":{"@type":"Person","name":"AnswerStack Editorial Team","worksFor":{"@type":"Organization","name":"AnswerStack"},"url":"https://www.answerstack.io/contributors/answer-stack"},"citation":[{"@type":"CreativeWork","name":"47 CFR Part 9, Subpart J: Next Generation 911","url":"https://www.ecfr.gov/current/title-47/chapter-I/subchapter-A/part-9/subpart-J"},{"@type":"CreativeWork","name":"Facilitating Implementation of Next Generation 911 Services (NG911); Location-Based Routing for Wireless 911 Calls (Report and Order, 89 FR 78066)","url":"https://www.federalregister.gov/documents/2024/09/24/2024-18603/facilitating-implementation-of-next-generation-911-services-ng911-location-based-routing-for"},{"@type":"CreativeWork","name":"Facilitating Implementation of Next Generation 911 Services (NG911); Improving 911 Reliability (Second Report and Order, 91 FR 42794)","url":"https://www.federalregister.gov/documents/2026/07/10/2026-13998/facilitating-implementation-of-next-generation-911-services-ng911-improving-911-reliability"},{"@type":"CreativeWork","name":"NENA i3 Standard for Next Generation 9-1-1 (NENA-STA-010.3e-2021)","url":"https://cdn.ymaws.com/www.nena.org/resource/resmgr/standards/NENA-STA-010.3e-2021_i3_Stan.pdf"},{"@type":"CreativeWork","name":"What is NG9-1-1?","url":"https://cdn.ymaws.com/www.nena.org/resource/resmgr/ng9-1-1_project/whatisng911.pdf"},{"@type":"CreativeWork","name":"47 CFR 9.10: 911 Service (wireless E911 Phase I and Phase II, indoor location accuracy)","url":"https://www.ecfr.gov/current/title-47/section-9.10"},{"@type":"CreativeWork","name":"47 CFR 9.11: E911 Service (interconnected VoIP)","url":"https://www.ecfr.gov/current/title-47/section-9.11"},{"@type":"CreativeWork","name":"47 CFR 9.16: General obligations, direct 911 dialing, notification, and dispatchable location","url":"https://www.ecfr.gov/current/title-47/section-9.16"},{"@type":"CreativeWork","name":"Location-Based Routing for Wireless 911 Calls (Report and Order, 89 FR 18488)","url":"https://www.federalregister.gov/documents/2024/03/13/2024-03157/location-based-routing-for-wireless-911-calls"},{"@type":"CreativeWork","name":"RFC 6881: Best Current Practice for Communications Services in Support of Emergency Calling","url":"https://www.rfc-editor.org/rfc/rfc6881.html"},{"@type":"CreativeWork","name":"Plan and manage emergency calling - Microsoft Teams","url":"https://learn.microsoft.com/en-us/microsoftteams/what-are-emergency-locations-addresses-and-call-routing"},{"@type":"CreativeWork","name":"NG911 Status","url":"https://www.nasna911.org/ng911-status"},{"@type":"CreativeWork","name":"How to Store Your 911 Location Data","url":"https://www.atlantech.net/blog/store-911-location-data-pidf-lo"}]}}}