VoIP and a landline both carry a phone call, but they use different networks to do it: a traditional landline sends your voice as an electrical signal over a dedicated copper circuit on the public switched telephone network, while VoIP converts your voice into digital packets that travel over a broadband internet connection.[1][2] That single difference drives the ones you actually notice. A landline draws its power from the phone company and keeps working in a blackout, whereas VoIP depends on your local electricity and internet, so it stops when either goes down.[2][8] VoIP usually costs less, adds features like mobile apps and voicemail-to-email, and grows in software rather than wiring, though it also follows different 911 rules because the network cannot always tell where a portable account is calling from.[3][5] In the United States, a VoIP service that both places and receives calls to the regular phone network is defined as 'interconnected VoIP' and must warn you where its 911 may be limited compared with traditional service.[1][5]
\n","summary":"A landline carries your voice as an electrical signal over a dedicated copper circuit on the traditional phone network, while VoIP sends it as digital packets over your broadband internet. That split drives the rest: a landline keeps working in a power outage and reports a fixed 911 address, while VoIP costs less, moves between devices, adds features like mobile apps and voicemail-to-email, and depends on your own power and internet. US rules class VoIP that reaches the phone network as 'interconnected VoIP,' with its own 911 duties.","publishedAt":"2026-07-18T03:27:24.417","verifiedAt":"2026-07-17T00:00:00","editorialStatus":"APPROVED","lastReviewedAt":"2026-07-17T00:00:00","nextReviewDueAt":"2026-10-17T00:00:00","templateVersion":"v2","aliases":["What is the difference between VoIP and a landline?","VoIP vs landline","Is VoIP better than a landline?","Difference between VoIP and traditional phone service","VoIP vs PSTN","How does VoIP compare to a landline?","Are VoIP and a landline the same thing?","VoIP or landline for business","Difference between an internet phone and a landline","Does VoIP work like a regular phone line?","VoIP versus a copper phone line","Should I switch from a landline to VoIP?"],"confidenceScore":90,"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":"99f0d8b5-6755-4949-ae85-bcfe3e10e8c0","sectionKey":"core_difference","sectionType":"markdown_section","heading":"What actually separates VoIP from a landline?","introMarkdown":"A landline and a VoIP line differ at the most basic level in how they move your voice from one place to another. A traditional landline, often called plain old telephone service or POTS, turns your voice into an electrical signal and sends it over a dedicated copper circuit that stays open for the length of the call, across the network known as the public switched telephone network, or PSTN.[2] VoIP, short for Voice over Internet Protocol, converts the same voice into digital data, breaks it into packets, and sends those packets over a broadband internet connection that also carries your email and web traffic.[1][2] A landline reserves a private lane for each call, while VoIP mixes voice into the general flow of internet data and reassembles it at the other end.\n\n### Why the underlying network changes everything\n\nMost of the practical differences people care about trace back to that one design choice. Because a landline runs on the phone company's own powered circuit, it works during a blackout and reports a fixed street address to 911 almost automatically.[2][5] Because VoIP runs over your internet connection, it depends on your power and your broadband, travels with you to any location, and needs software rather than physical wiring to add a line or a feature.[2][3] Signaling protocols such as the Session Initiation Protocol set up and tear down each VoIP call, and the audio itself rides in a separate stream, which is what lets a call start on a laptop and still reach an ordinary phone number.[4] Neither approach is simply better than the other, because they trade the landline's self-powered reliability against the flexibility and lower cost that VoIP tends to offer, and the right fit depends on what a given line is for.","introHtml":"A landline and a VoIP line differ at the most basic level in how they move your voice from one place to another. A traditional landline, often called plain old telephone service or POTS, turns your voice into an electrical signal and sends it over a dedicated copper circuit that stays open for the length of the call, across the network known as the public switched telephone network, or PSTN.[2] VoIP, short for Voice over Internet Protocol, converts the same voice into digital data, breaks it into packets, and sends those packets over a broadband internet connection that also carries your email and web traffic.[1][2] A landline reserves a private lane for each call, while VoIP mixes voice into the general flow of internet data and reassembles it at the other end.
\nMost of the practical differences people care about trace back to that one design choice. Because a landline runs on the phone company's own powered circuit, it works during a blackout and reports a fixed street address to 911 almost automatically.[2][5] Because VoIP runs over your internet connection, it depends on your power and your broadband, travels with you to any location, and needs software rather than physical wiring to add a line or a feature.[2][3] Signaling protocols such as the Session Initiation Protocol set up and tear down each VoIP call, and the audio itself rides in a separate stream, which is what lets a call start on a laptop and still reach an ordinary phone number.[4] Neither approach is simply better than the other, because they trade the landline's self-powered reliability against the flexibility and lower cost that VoIP tends to offer, and the right fit depends on what a given line is for.
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":0},{"id":"64996400-8f26-439f-bb52-120dec68011e","sectionKey":"comparison_table","sectionType":"table_section","heading":"How VoIP and a landline compare at a glance","introMarkdown":"The table sums up the main differences, and the sections after it explain each one and what to do about it.","introHtml":"The table sums up the main differences, and the sections after it explain each one and what to do about it.
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{"rows":[{"cells":["Underlying network","Circuit-switched copper on the PSTN, one dedicated line per call [2]","Packet-switched digital audio over broadband internet [1][2]"]},{"cells":["What it needs to work","The phone company's own line power, no internet required [2]","Local electricity plus a working broadband connection [2]"]},{"cells":["Behavior in an outage","Usually keeps a dial tone in a power or internet failure [2]","Calls drop when power or internet goes down [2][8]"]},{"cells":["911 and caller location","Reports a fixed address to emergency services almost automatically [5]","Must supply dispatchable or registered location, and can be limited for portable accounts [5][6]"]},{"cells":["Cost","Higher monthly fees, per-minute long distance [2][3]","Lower monthly fees, long distance often included [2][3]"]},{"cells":["Features and mobility","Basic calling, tied to one physical location [8]","Apps, voicemail-to-email, and one number across devices [3]"]}],"columns":["Dimension","Traditional landline","VoIP"]},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":1},{"id":"e8c6cb89-fe85-4729-8e2a-18863ee50c85","sectionKey":"how_voice_moves","sectionType":"markdown_section","heading":"How each one moves your voice","introMarkdown":"The clearest difference is the path your voice takes. A landline is a circuit-switched system: when you dial, the network opens one continuous electrical circuit between you and the other phone and holds it open until someone hangs up, so the line is yours alone for the whole call.[2] VoIP is packet-switched, which means it samples your voice, compresses it, and splits it into small digital packets that travel over your internet connection alongside other data, then reassembles them at the far end.[1][2] Because the audio is just data, a VoIP packet stream can start on a computer or a mobile app and still reach a normal phone number once it passes through a gateway that hands the call to the traditional network.[1] The Session Initiation Protocol, usually shortened to SIP, does the work of finding the other party and starting or ending the call, while the voice rides in a separate media stream.[4] For you, the practical result is that a landline gives every call a private, dedicated lane, whereas VoIP shares one connection across all your calls and data, which is more efficient but also means voice now competes with everything else on your network.","introHtml":"The clearest difference is the path your voice takes. A landline is a circuit-switched system: when you dial, the network opens one continuous electrical circuit between you and the other phone and holds it open until someone hangs up, so the line is yours alone for the whole call.[2] VoIP is packet-switched, which means it samples your voice, compresses it, and splits it into small digital packets that travel over your internet connection alongside other data, then reassembles them at the far end.[1][2] Because the audio is just data, a VoIP packet stream can start on a computer or a mobile app and still reach a normal phone number once it passes through a gateway that hands the call to the traditional network.[1] The Session Initiation Protocol, usually shortened to SIP, does the work of finding the other party and starting or ending the call, while the voice rides in a separate media stream.[4] For you, the practical result is that a landline gives every call a private, dedicated lane, whereas VoIP shares one connection across all your calls and data, which is more efficient but also means voice now competes with everything else on your network.
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":2},{"id":"4d46d143-2cad-45d4-9bb4-1047567553ab","sectionKey":"power_and_outages","sectionType":"markdown_section","heading":"What each needs to work, and what happens in an outage","introMarkdown":"A landline keeps working when the power fails and a VoIP phone usually does not, which is the difference most people feel first. Traditional phone service is powered over the copper line itself from the phone company's central office, so a basic corded landline holds a dial tone during a blackout without any battery at your location.[2] VoIP depends on two things you supply, local electricity for your phone, router, and modem, and a working broadband connection, so a power cut or an internet outage takes the service down with it.[2][8] This is why providers often recommend a battery backup for the router and a mobile phone as a fallback for emergencies.[8] It also shapes call quality in normal use, because voice packets are sensitive to delay and loss in a way that a dedicated circuit is not, so a congested or unreliable internet connection can make a VoIP call sound choppy even when a landline on the same premises would stay steady.[2] None of this makes VoIP fragile by default; it means the reliability now rests on the network and power you run it over, rather than on the phone company alone.","introHtml":"A landline keeps working when the power fails and a VoIP phone usually does not, which is the difference most people feel first. Traditional phone service is powered over the copper line itself from the phone company's central office, so a basic corded landline holds a dial tone during a blackout without any battery at your location.[2] VoIP depends on two things you supply, local electricity for your phone, router, and modem, and a working broadband connection, so a power cut or an internet outage takes the service down with it.[2][8] This is why providers often recommend a battery backup for the router and a mobile phone as a fallback for emergencies.[8] It also shapes call quality in normal use, because voice packets are sensitive to delay and loss in a way that a dedicated circuit is not, so a congested or unreliable internet connection can make a VoIP call sound choppy even when a landline on the same premises would stay steady.[2] None of this makes VoIP fragile by default; it means the reliability now rests on the network and power you run it over, rather than on the phone company alone.
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":3},{"id":"233c2eb0-25b3-4089-8afc-1cbe0f44126b","sectionKey":"emergency_calling","sectionType":"markdown_section","heading":"How 911 and caller location differ","introMarkdown":"With a landline, emergency services receive a fixed street address for your line almost automatically, while VoIP has to work harder to tell 911 where you are. A traditional wired phone is tied to one physical address, so a 911 call from it arrives with location already attached.[5] A VoIP account can travel to any internet connection, so the network cannot assume where a call is coming from. US rules address this by defining 'interconnected VoIP,' any service that both places and receives calls to the public phone network, and requiring those providers to deliver a call-back number and location to the 911 center and to tell you plainly where their 911 might be limited compared with traditional service.[1][5]\n\n### Location rules and dates\n\nFixed VoIP services have had to supply an automated dispatchable location, meaning a validated street address plus details such as a floor or suite, since January 6, 2021, with portable services following on January 6, 2022.[6] For a softphone or an app that moves between locations, the service may fall back on the Registered Location you entered, so keeping that address current is what makes emergency calls land in the right place.[5][6] A related rule, Kari's Law, requires many multi-line phone systems installed after February 16, 2020 to allow direct 911 dialing with no prefix.[6]","introHtml":"With a landline, emergency services receive a fixed street address for your line almost automatically, while VoIP has to work harder to tell 911 where you are. A traditional wired phone is tied to one physical address, so a 911 call from it arrives with location already attached.[5] A VoIP account can travel to any internet connection, so the network cannot assume where a call is coming from. US rules address this by defining 'interconnected VoIP,' any service that both places and receives calls to the public phone network, and requiring those providers to deliver a call-back number and location to the 911 center and to tell you plainly where their 911 might be limited compared with traditional service.[1][5]
\nFixed VoIP services have had to supply an automated dispatchable location, meaning a validated street address plus details such as a floor or suite, since January 6, 2021, with portable services following on January 6, 2022.[6] For a softphone or an app that moves between locations, the service may fall back on the Registered Location you entered, so keeping that address current is what makes emergency calls land in the right place.[5][6] A related rule, Kari's Law, requires many multi-line phone systems installed after February 16, 2020 to allow direct 911 dialing with no prefix.[6]
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":4},{"id":"cf41d56e-98a2-4989-bcf7-1fc0c506c93d","sectionKey":"cost_comparison","sectionType":"markdown_section","heading":"How the costs compare","introMarkdown":"VoIP is generally cheaper to run than a landline, mostly because it does not depend on dedicated circuits and separate long-distance billing. Landline plans tend to carry higher monthly fees and charge per minute for long-distance and international calls, and adding capacity usually means paying for more physical lines and hardware.[2] With VoIP, monthly fees are typically lower, long-distance and international calls are often included or billed at much lower rates, and the same broadband connection you already pay for carries the calls.[2][3] Business VoIP is commonly sold per user per month, with entry plans starting around fifteen dollars a user, so the cost scales with headcount rather than with wiring.[2] The savings are not automatic in every case, since VoIP assumes you have enough reliable bandwidth, and a business that has to upgrade its internet or add backup power to support voice should count that in the comparison. For most organizations the recurring cost still lands lower than an equivalent set of traditional lines, especially once long-distance usage is included.[2][3]","introHtml":"VoIP is generally cheaper to run than a landline, mostly because it does not depend on dedicated circuits and separate long-distance billing. Landline plans tend to carry higher monthly fees and charge per minute for long-distance and international calls, and adding capacity usually means paying for more physical lines and hardware.[2] With VoIP, monthly fees are typically lower, long-distance and international calls are often included or billed at much lower rates, and the same broadband connection you already pay for carries the calls.[2][3] Business VoIP is commonly sold per user per month, with entry plans starting around fifteen dollars a user, so the cost scales with headcount rather than with wiring.[2] The savings are not automatic in every case, since VoIP assumes you have enough reliable bandwidth, and a business that has to upgrade its internet or add backup power to support voice should count that in the comparison. For most organizations the recurring cost still lands lower than an equivalent set of traditional lines, especially once long-distance usage is included.[2][3]
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":5},{"id":"fb65ca12-cc63-4d8c-87ab-6a5f8e157cbf","sectionKey":"features_and_mobility","sectionType":"markdown_section","heading":"What VoIP can do that a landline cannot","introMarkdown":"Beyond price, the biggest practical gap is what VoIP can do that a landline cannot. A landline handles voice calls from one fixed location, with extras like voicemail or caller ID often sold as add-ons.[2][8] VoIP treats a call as data, so the same account can ring on a desk phone, a laptop, and a smartphone app under one number, which lets someone take work calls from home or on the road without giving out a personal number.[3] Standard business VoIP plans usually bundle voicemail-to-email, call forwarding, auto-attendants, call recording, and connections to tools like CRM software, features a traditional line does not offer on its own.[2][8] VoIP also lives inside broader unified communications packages that combine calling with video meetings, messaging, and voicemail delivered by email, so voice becomes one part of a single system rather than a separate service.[3] Adding a line or a feature is a change in software rather than a new physical circuit, which is why a VoIP system scales up or down far faster than a landline that needs new wiring for each addition.[2]","introHtml":"Beyond price, the biggest practical gap is what VoIP can do that a landline cannot. A landline handles voice calls from one fixed location, with extras like voicemail or caller ID often sold as add-ons.[2][8] VoIP treats a call as data, so the same account can ring on a desk phone, a laptop, and a smartphone app under one number, which lets someone take work calls from home or on the road without giving out a personal number.[3] Standard business VoIP plans usually bundle voicemail-to-email, call forwarding, auto-attendants, call recording, and connections to tools like CRM software, features a traditional line does not offer on its own.[2][8] VoIP also lives inside broader unified communications packages that combine calling with video meetings, messaging, and voicemail delivered by email, so voice becomes one part of a single system rather than a separate service.[3] Adding a line or a feature is a change in software rather than a new physical circuit, which is why a VoIP system scales up or down far faster than a landline that needs new wiring for each addition.[2]
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":6},{"id":"4869f4f1-ed6c-454d-9f6f-6a0ead992b2f","sectionKey":"copper_retirement","sectionType":"markdown_section","heading":"Why the landline network itself is being retired","introMarkdown":"The comparison is also shifting because the copper network behind traditional landlines is being phased out. Carriers are retiring the aging copper infrastructure that POTS depends on and moving customers to IP-based services, VoIP among them. AT&T stopped accepting new orders for copper-based service in October 2025 and plans to begin decommissioning copper facilities in roughly 500 wire centers, about ten percent of its footprint, starting in June 2026, with the rest phased out through 2029.[7] Other carriers are following similar timelines.[7] For a business, this means keeping a pure copper landline is becoming harder and, in many areas, will stop being an option, so the practical question is often which IP-based replacement to move to rather than whether to keep the old line. If you still rely on copper lines for phones, alarm panels, elevators, or fax, it is worth checking your carrier's retirement schedule for your area and planning the switch before a forced cutover.[7]","introHtml":"The comparison is also shifting because the copper network behind traditional landlines is being phased out. Carriers are retiring the aging copper infrastructure that POTS depends on and moving customers to IP-based services, VoIP among them. AT&T stopped accepting new orders for copper-based service in October 2025 and plans to begin decommissioning copper facilities in roughly 500 wire centers, about ten percent of its footprint, starting in June 2026, with the rest phased out through 2029.[7] Other carriers are following similar timelines.[7] For a business, this means keeping a pure copper landline is becoming harder and, in many areas, will stop being an option, so the practical question is often which IP-based replacement to move to rather than whether to keep the old line. If you still rely on copper lines for phones, alarm panels, elevators, or fax, it is worth checking your carrier's retirement schedule for your area and planning the switch before a forced cutover.[7]
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":7},{"id":"e1091eee-1228-4bec-8fe7-9703db0c5200","sectionKey":"trade_offs","sectionType":"markdown_section","heading":"Trade-offs and what to watch","introMarkdown":"Choosing between VoIP and a landline comes down to a few trade-offs worth naming plainly.\n\n### Reliability during outages\n\nA landline's main advantage is that it keeps working when the power or the internet is down, which still matters for emergency lines, elevators, and alarm circuits.[2] If you move those to VoIP, plan for battery backup and a cellular fallback so a blackout does not cut off a critical line.[2][8]\n\n### Call quality depends on your network\n\nVoIP audio is only as steady as the connection under it, so a business with thin or congested bandwidth can hear the difference.[2] Giving voice traffic priority on the network and confirming you have enough upload capacity for the number of simultaneous calls is what keeps quality close to a landline's.\n\n### 911 needs attention for portable accounts\n\nBecause a VoIP number can travel, the address 911 sees is only as accurate as the one on file, so any account used from changing locations needs its Registered Location kept current.[5][6]\n\n### Fewer places still offer copper\n\nAs carriers retire copper, a traditional landline is becoming harder to buy or keep in many areas, which narrows the choice over time to which IP-based service to use.[7]","introHtml":"Choosing between VoIP and a landline comes down to a few trade-offs worth naming plainly.
\nA landline's main advantage is that it keeps working when the power or the internet is down, which still matters for emergency lines, elevators, and alarm circuits.[2] If you move those to VoIP, plan for battery backup and a cellular fallback so a blackout does not cut off a critical line.[2][8]
\nVoIP audio is only as steady as the connection under it, so a business with thin or congested bandwidth can hear the difference.[2] Giving voice traffic priority on the network and confirming you have enough upload capacity for the number of simultaneous calls is what keeps quality close to a landline's.
\nBecause a VoIP number can travel, the address 911 sees is only as accurate as the one on file, so any account used from changing locations needs its Registered Location kept current.[5][6]
\nAs carriers retire copper, a traditional landline is becoming harder to buy or keep in many areas, which narrows the choice over time to which IP-based service to use.[7]
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":8},{"id":"43fcf10f-e409-4f75-aa50-be7b18149be3","sectionKey":"what_it_is_not","sectionType":"markdown_section","heading":"What this comparison is not","introMarkdown":"A few common mix-ups make the VoIP-versus-landline question murkier than it needs to be.\n\n### 'Landline' does not always mean copper\n\nMany phone lines sold as landlines today are already digital underneath, delivered over fiber or cable rather than the original copper circuit.[7] The clean copper-versus-internet split describes the traditional case, but a modern home phone from a cable company is often VoIP with a landline label.\n\n### VoIP is not the same as a cell phone\n\nA mobile call travels wirelessly over a carrier's cellular network, and although modern mobile voice uses IP inside that network, it is provisioned and billed differently from the interconnected VoIP service these rules describe.[1] VoIP rides your own internet connection instead of a cellular one.\n\n### VoIP is not a single app or brand\n\nConsumer calling apps are one way to use VoIP, but the term covers a whole category that also includes desk phones, carrier trunks, and full business phone systems.[1] Two VoIP services can share none of the same software and still both be VoIP.\n\n### Cheaper does not mean lower quality\n\nVoIP usually costs less, but that reflects a more efficient use of the network rather than a downgrade, and on a solid connection a wideband VoIP call can carry a fuller, clearer voice than a narrowband landline.[2]","introHtml":"A few common mix-ups make the VoIP-versus-landline question murkier than it needs to be.
\nMany phone lines sold as landlines today are already digital underneath, delivered over fiber or cable rather than the original copper circuit.[7] The clean copper-versus-internet split describes the traditional case, but a modern home phone from a cable company is often VoIP with a landline label.
\nA mobile call travels wirelessly over a carrier's cellular network, and although modern mobile voice uses IP inside that network, it is provisioned and billed differently from the interconnected VoIP service these rules describe.[1] VoIP rides your own internet connection instead of a cellular one.
\nConsumer calling apps are one way to use VoIP, but the term covers a whole category that also includes desk phones, carrier trunks, and full business phone systems.[1] Two VoIP services can share none of the same software and still both be VoIP.
\nVoIP usually costs less, but that reflects a more efficient use of the network rather than a downgrade, and on a solid connection a wideband VoIP call can carry a fuller, clearer voice than a narrowband landline.[2]
\n","outroMarkdown":null,"outroHtml":null,"contentJson":{},"configJson":{},"noteMarkdown":null,"noteHtml":null,"sortOrder":9},{"id":"494661c4-4d40-4e3a-b8eb-4f12d55a8f2a","sectionKey":"contributor_perspective","sectionType":"markdown_section","heading":"How this answer was researched","introMarkdown":"This entry draws its technical and regulatory claims from primary sources and its market claims from independent industry references. The definition of interconnected VoIP and the emergency-calling duties come from the Code of Federal Regulations, and the SIP signaling detail comes from the IETF document that specifies it.[1][4][5] The compliance dates for dispatchable location and direct 911 dialing are drawn from a legal summary of the FCC orders that set them.[6] The comparisons of cost, features, power dependence, and network design are attributed to independent telecom sources rather than stated as blanket facts, and the copper-retirement timeline reflects publicly reported carrier schedules.[2][3][7][8] Telecom products, prices, and rules change, so the dates and figures here reflect what the cited sources said on the verification date. Practitioners who install, regulate, or support business phone systems are welcome to suggest corrections or additions, which are checked against primary sources before any update.","introHtml":"This entry draws its technical and regulatory claims from primary sources and its market claims from independent industry references. The definition of interconnected VoIP and the emergency-calling duties come from the Code of Federal Regulations, and the SIP signaling detail comes from the IETF document that specifies it.[1][4][5] The compliance dates for dispatchable location and direct 911 dialing are drawn from a legal summary of the FCC orders that set them.[6] The comparisons of cost, features, power dependence, and network design are attributed to independent telecom sources rather than stated as blanket facts, and the copper-retirement timeline reflects publicly reported carrier schedules.[2][3][7][8] Telecom products, prices, and rules change, so the dates and figures here reflect what the cited sources said on the verification date. Practitioners who install, regulate, or support business phone systems are welcome to suggest corrections or additions, which are checked against primary sources before any update.
\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":10}],"citations":[{"title":"47 CFR 9.3, Definitions: Interconnected VoIP service","url":"https://www.law.cornell.edu/cfr/text/47/9.3","excerpt":"Enables real-time, two-way voice communications; requires a broadband connection from the user's location; requires internet protocol-compatible customer premises equipment; and permits users generally to receive calls that originate on the public switched telephone network and to terminate calls to the public switched telephone network.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"Regulatory definition of interconnected VoIP: real-time two-way voice, broadband from the user's location, IP-compatible customer premises equipment, and calls to and from the PSTN","domain":"law.cornell.edu","publisherName":"Legal Information Institute, Cornell Law School"},{"title":"VoIP vs. Landline: Which Is Better for Your Business?","url":"https://www.nextiva.com/blog/voip-vs-landline.html","excerpt":"Voice over IP... works by converting sound into data packets or digital signals and transmits them to a VoIP provider. Landlines can remain operational during internet and electricity failures.","quoteText":null,"sourceRole":"INDEPENDENT","verifiedAt":"2026-07-17T00:00:00","supportsText":"Landline is circuit-switched copper POTS while VoIP converts sound into data packets over the internet; lower VoIP cost and per-user pricing; VoIP features and faster scaling; landlines keep working in a power or internet outage while VoIP calls drop","domain":"nextiva.com","publisherName":"Nextiva"},{"title":"What is VoIP and how does it work?","url":"https://www.business.att.com/learn/tech-advice/what-is-voip-and-how-does-it-work-.html","excerpt":"Today you can make phone calls anytime, anywhere using an Internet-connected computer, a headset, and voice over IP (VoIP). Long-distance and international calls are generally free with VoIP service.","quoteText":null,"sourceRole":"INDEPENDENT","verifiedAt":"2026-07-17T00:00:00","supportsText":"VoIP mobility (call from anywhere on an internet connection), long-distance and international calls generally free with VoIP, and unified communications bundling calls with voicemail, email, and web conferences","domain":"business.att.com","publisherName":"AT&T Business"},{"title":"RFC 3261: SIP: Session Initiation Protocol","url":"https://datatracker.ietf.org/doc/html/rfc3261","excerpt":"an application-layer control (signaling) protocol for creating, modifying, and terminating sessions with one or more participants. These sessions include Internet telephone calls.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"SIP is the application-layer signaling protocol that creates, modifies, and ends VoIP sessions such as internet telephone calls","domain":"datatracker.ietf.org","publisherName":"IETF"},{"title":"47 CFR 9.11: E911 service requirements for interconnected VoIP","url":"https://www.law.cornell.edu/cfr/text/47/9.11","excerpt":"shall specifically advise every subscriber, both new and existing, prominently and in plain language, of the circumstances under which E911 service may not be available through the interconnected VoIP service or may be in some way limited by comparison to traditional E911 service.","quoteText":null,"sourceRole":"PRIMARY","verifiedAt":"2026-07-17T00:00:00","supportsText":"Interconnected VoIP E911 duties: transmit all 911 calls with call-back number and dispatchable or registered location, and advise subscribers where E911 may be limited by comparison to traditional E911 service","domain":"law.cornell.edu","publisherName":"Legal Information Institute, Cornell Law School"},{"title":"FCC Announces Compliance Dates for New E911 Rules Applicable to Multi-Line Telephone Systems and VoIP Providers","url":"https://www.wiley.law/alert-FCC-Announces-Compliance-Dates-for-New-E911-Rules-Applicable-to-Multi-Line-Telephone-Systems-and-VoIP-Providers","excerpt":"Fixed services: automated dispatchable location with each 911 call starting January 6, 2021. Non-fixed services: January 6, 2022.","quoteText":null,"sourceRole":"INDEPENDENT","verifiedAt":"2026-07-17T00:00:00","supportsText":"Compliance dates: fixed interconnected VoIP dispatchable location by January 6, 2021; non-fixed by January 6, 2022; Kari's Law direct 911 dialing for multi-line systems installed after February 16, 2020","domain":"wiley.law","publisherName":"Wiley Rein LLP"},{"title":"The Complete PSTN Copper Shutdown Timeline: What Business Owners Need to Know in 2026","url":"https://www.phonewire.com/blog/33010","excerpt":"October 2025: AT&T stopped accepting new orders or changes for copper-based services. June 2026: AT&T begins decommissioning copper facilities in approximately 500 wire centers nationwide.","quoteText":null,"sourceRole":"INDEPENDENT","verifiedAt":"2026-07-17T00:00:00","supportsText":"Copper retirement timeline: AT&T stopped accepting new copper orders in October 2025 and begins decommissioning copper in about 500 wire centers, roughly ten percent of its footprint, in June 2026, with the rest phased out through 2029; other carriers on similar timelines","domain":"phonewire.com","publisherName":"Phonewire"},{"title":"VoIP vs. Landline for Business Phone Service: Which Is Best?","url":"https://www.atlantech.net/blog/voip-vs.-landline-for-business-phone-service-which-is-best","excerpt":"VOIP entails using a special adaptor that connects to your internet service, rather than using the usual telephone lines. Landline phone service is not connected to electricity... in the event of a power outage, you would not lose phone service.","quoteText":null,"sourceRole":"SUPPORTING","verifiedAt":"2026-07-17T00:00:00","supportsText":"VoIP connects through an internet adaptor rather than telephone lines, VoIP does not work during a power outage while a landline is not dependent on electricity, and standard business VoIP features; corroborated by [2] and [3]","domain":"atlantech.net","publisherName":"Atlantech Online"}],"revisions":[],"relatedAnswers":[{"id":"2bc2d203-d1bf-4685-91a1-cd586dddf234","slug":"do-i-need-a-phone-line-for-voip","question":"Do I need a phone line for VoIP?","publishedAt":"2026-07-18T03:33:04.199","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":"voip","label":"VoIP","description":"Voice over IP for business: how it works, what it requires, and how it compares to traditional phone service.","schemaKind":null},"contributor":{"id":"ec39deab-44fe-48d8-9029-fefe993ab85a","slug":"answer-stack","displayName":"AnswerStack","websiteUrl":null},"snippet":"VoIP replaces the phone line with a broadband internet connection, not dial-tone service. You need bandwidth of about 85 to 100 kbps per call and a device to talk on: an IP phone, a softphone app, or a regular phone on an adapter. You can keep your existing landline number by porting it. The real trade-offs are power and internet dependence, which battery backup helps cover, and 911 that routes to an address you register.","url":"/q/do-i-need-a-phone-line-for-voip"},{"id":"316da151-4ac7-4ec8-9c85-ce74f5593693","slug":"do-i-need-a-special-phone-for-voip","question":"Do I need a special phone for VoIP?","publishedAt":"2026-07-18T03:30:09.851","confidenceScore":90,"confidenceLabel":"High","industry":{"id":"ff619d7c-d7d7-485e-a05a-53fba07f33ed","slug":"telecommunications","label":"Telecommunications","description":"Business voice, fiber, UCaaS, and network services"},"topic":{"slug":"voip","label":"VoIP","description":"Voice over IP for business: how it works, what it requires, and how it compares to traditional phone service.","schemaKind":null},"contributor":{"id":"ec39deab-44fe-48d8-9029-fefe993ab85a","slug":"answer-stack","displayName":"AnswerStack","websiteUrl":null},"snippet":"A dedicated VoIP handset is optional. The same call can run through a softphone app on a phone or laptop, a purpose-built IP desk phone, a web browser using WebRTC, or your current analog phone plugged into an adapter. Each path needs an internet connection and equipment that can speak VoIP. Certified or approved phones exist for full feature support, but any SIP-compliant device generally works, and a whole team can pilot VoIP on hardware people already own.","url":"/q/do-i-need-a-special-phone-for-voip"},{"id":"0ef1cfdf-0d57-4903-8eb6-b422a49ece05","slug":"what-type-of-internet-connection-do-i-need-for-voip","question":"What type of internet connection do I need for VoIP?","publishedAt":"2026-07-18T03:27:41.235","confidenceScore":90,"confidenceLabel":"High","industry":{"id":"ff619d7c-d7d7-485e-a05a-53fba07f33ed","slug":"telecommunications","label":"Telecommunications","description":"Business voice, fiber, UCaaS, and network services"},"topic":{"slug":"voip","label":"VoIP","description":"Voice over IP for business: how it works, what it requires, and how it compares to traditional phone service.","schemaKind":null},"contributor":{"id":"ec39deab-44fe-48d8-9029-fefe993ab85a","slug":"answer-stack","displayName":"AnswerStack","websiteUrl":null},"snippet":"A VoIP call needs very little bandwidth, roughly 100 kbps in each direction, so the deciding factors are upload capacity and network quality rather than raw download speed. Aim for latency under 150 ms, jitter under 30 ms, and packet loss under 1 percent, and size the link to your peak number of simultaneous calls. Fiber, cable, DSL, fixed wireless, and low-orbit satellite can all carry voice; symmetrical fiber handles many concurrent lines best, while geostationary satellite adds too much delay.","url":"/q/what-type-of-internet-connection-do-i-need-for-voip"},{"id":"a96e1365-05b5-48e7-94dd-91a34d711268","slug":"does-voip-require-an-internet-connection","question":"Does VoIP require an internet connection?","publishedAt":"2026-07-18T03:26:50.582","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":"voip","label":"VoIP","description":"Voice over IP for business: how it works, what it requires, and how it compares to traditional phone service.","schemaKind":null},"contributor":{"id":"ec39deab-44fe-48d8-9029-fefe993ab85a","slug":"answer-stack","displayName":"AnswerStack","websiteUrl":null},"snippet":"VoIP carries calls as data over an IP network, so it needs connectivity to work. For any service that reaches outside callers or the public phone network, that means a broadband connection, though the link can be wired, Wi-Fi, or cellular data. The one exception is internal extension-to-extension calling, which can stay on a private LAN with no internet at all. Because calls ride your data connection and local power, VoIP also stops during an internet or power outage unless you plan backup power and failover.","url":"/q/does-voip-require-an-internet-connection"}],"contributorStats":{"verifiedAnswers":224,"openDisputes":0},"schemaJson":{"@context":"https://schema.org","@type":"Question","name":"How is VoIP different from a landline?","text":"How is VoIP different from a landline?","url":"https://www.answerstack.io/q/how-is-voip-different-from-a-landline","answerCount":1,"datePublished":"2026-07-18T03:27:24.417","author":{"@type":"Person","name":"AnswerStack Editorial Team","worksFor":{"@type":"Organization","name":"AnswerStack"},"url":"https://www.answerstack.io/contributors/answer-stack"},"about":[{"@type":"Thing","name":"VoIP"},{"@type":"Thing","name":"Telecommunications"}],"acceptedAnswer":{"@type":"Answer","text":"VoIP and a landline both carry a phone call, but they use different networks to do it: a traditional landline sends your voice as an electrical signal over a dedicated copper circuit on the public switched telephone network, while VoIP converts your voice into digital packets that travel over a broadband internet connection.[1][2] That single difference drives the ones you actually notice. A landline draws its power from the phone company and keeps working in a blackout, whereas VoIP depends on your local electricity and internet, so it stops when either goes down.[2][8] VoIP usually costs less, adds features like mobile apps and voicemail-to-email, and grows in software rather than wiring, though it also follows different 911 rules because the network cannot always tell where a portable account is calling from.[3][5] In the United States, a VoIP service that both places and receives calls to the regular phone network is defined as 'interconnected VoIP' and must warn you where its 911 may be limited compared with traditional service.[1][5]","url":"https://www.answerstack.io/q/how-is-voip-different-from-a-landline","upvoteCount":0,"datePublished":"2026-07-18T03:27:24.417","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 9.3, Definitions: Interconnected VoIP service","url":"https://www.law.cornell.edu/cfr/text/47/9.3"},{"@type":"CreativeWork","name":"VoIP vs. Landline: Which Is Better for Your Business?","url":"https://www.nextiva.com/blog/voip-vs-landline.html"},{"@type":"CreativeWork","name":"What is VoIP and how does it work?","url":"https://www.business.att.com/learn/tech-advice/what-is-voip-and-how-does-it-work-.html"},{"@type":"CreativeWork","name":"RFC 3261: SIP: Session Initiation Protocol","url":"https://datatracker.ietf.org/doc/html/rfc3261"},{"@type":"CreativeWork","name":"47 CFR 9.11: E911 service requirements for interconnected VoIP","url":"https://www.law.cornell.edu/cfr/text/47/9.11"},{"@type":"CreativeWork","name":"FCC Announces Compliance Dates for New E911 Rules Applicable to Multi-Line Telephone Systems and VoIP Providers","url":"https://www.wiley.law/alert-FCC-Announces-Compliance-Dates-for-New-E911-Rules-Applicable-to-Multi-Line-Telephone-Systems-and-VoIP-Providers"},{"@type":"CreativeWork","name":"The Complete PSTN Copper Shutdown Timeline: What Business Owners Need to Know in 2026","url":"https://www.phonewire.com/blog/33010"},{"@type":"CreativeWork","name":"VoIP vs. Landline for Business Phone Service: Which Is Best?","url":"https://www.atlantech.net/blog/voip-vs.-landline-for-business-phone-service-which-is-best"}]}}}