What is the difference between Direct Routing and Operator Connect?

Direct Routing and Operator Connect both solve the same problem: giving a Teams Phone user a real phone number and a path to the public switched telephone network (PSTN) so they can call landlines and mobiles.[1] Teams handles the call control and the private branch exchange (PBX) features, but it does not supply the phone line itself, so every deployment needs a separate PSTN connection on top of the Teams Phone license.[6] Direct Routing and Operator Connect are two of the four ways Microsoft lets you make that connection, alongside its own Calling Plan and Teams Phone Mobile.[1]

The split is about who runs the connection

The difference between them is not what the user experiences on a call, which is effectively the same, but who owns and operates the plumbing behind it. Operator Connect hands the carrier relationship and the session border controllers to a Microsoft-certified operator, so the hardware and much of the support sit with them.[2] Direct Routing keeps that responsibility with you: you choose the carrier, and you (or an integrator, or a Direct-Routing-as-a-Service provider) run a certified session border controller, or SBC, that bridges your carrier's trunk to Teams.[1][3]

Both start from the same license

Neither model replaces the Teams Phone license; both sit underneath it. A user has to be Teams Phone licensed and, for these two models, in TeamsOnly mode before any number will work.[2][3] Because the models are configuration options rather than separate products, a single organization can run Operator Connect for some users and Direct Routing for others, which is common once you account for different offices, carriers, and legacy equipment.[1][6]

The session border controller is the dividing line between the two models. With Operator Connect, the certified operator owns and manages the SBCs and the PSTN calling service, which is why Microsoft describes it as operator-managed infrastructure that saves you the hardware purchase and its upkeep.[2][11] You never pair an SBC, install a certificate, or patch firmware, because that layer belongs to the operator's network.[2][7]

Direct Routing puts the SBC in your hands. You connect a supported, customer-provided SBC to Teams Phone, and that device, whether it is a physical appliance in your data center or a virtual instance, is procured, installed, and managed by you, your integrator, or a Direct-Routing-as-a-Service provider.[1][3] Microsoft only supports Direct Routing with SBCs it has certified, from vendors such as AudioCodes, Ribbon, Oracle, Cisco, and TE-SYSTEMS, so the hardware choice is constrained even though the carrier is not.[4] Running that SBC brings real work: a public certificate from a trusted authority, DNS records and an FQDN that matches a domain in your tenant, firewall rules for Microsoft's signaling and media ranges, and firmware kept at a supported version.[3] For a team without telephony engineers, a managed SBC service moves that burden to a provider while keeping the any-carrier flexibility Direct Routing is usually chosen for.[1]

Operator Connect limits you to carriers that have joined Microsoft's Operator Connect program, while Direct Routing works with practically any carrier. With Operator Connect, you pick from the operators listed in the Microsoft 365 Operator Connect directory for your country, so the choice depends on which providers have completed certification where you operate.[2] The upside is that a participating operator has already built and tested the integration, so you keep your preferred provider or find a new one and let them run the service.[2]

Direct Routing removes the certification gate on the carrier side. Because you connect your own SBC to almost any telephony trunk, you can use a PSTN operator that has no relationship with Microsoft at all, keep an existing carrier contract, or combine several carriers behind one deployment.[3] That is the practical reason organizations pick Direct Routing when their carrier is not in the Operator Connect program, when a regulator requires a specific local provider, or when they want to consolidate carriers they already hold.[1][3] The trade is that the carrier's integration becomes your responsibility to configure and maintain rather than something the operator delivers ready-made.[7][8]

Operator Connect is the lighter setup by a wide margin. After you choose an operator in the Teams admin center under Voice and Operator Connect, select your countries, and share contact details, the operator uploads numbers to your tenant and you assign them to users from the same console, often within minutes.[5] There is no SBC to pair and no routing policy to write, so much of the deployment reduces to picking an operator and assigning numbers.[5][9]

Direct Routing asks for more upfront and continuing work because you are standing up the connection yourself. Configuration runs through the Teams admin center or PowerShell and includes pairing the SBC by its FQDN, voice-enabling users, and building the call routing with voice routes, PSTN usages, and voice routing policies.[3] You also own the ongoing maintenance: renewing the SBC certificate before it expires, tracking certified firmware versions, and adjusting routing as numbers and sites change.[3][4] Independent guides consistently describe Direct Routing as the more complex option to deploy and Operator Connect as the faster one, which matches Microsoft's own framing of operator-managed versus customer-managed connectivity.[7][10]

Direct Routing gives you the most control over call routing and the widest integration with existing telephony, which is its main reason to exist. Because you own the SBC and the voice routing policies, you can write granular rules, apply location-based routing to restrict toll bypass, and connect Teams to a third-party PBX, a contact center, analog devices, or overhead paging.[1][3] A common pattern routes calls to phones on a legacy PBX through Direct Routing so they stay inside the enterprise network rather than crossing the PSTN, while other calls exit through whatever carrier is assigned to the user.[3]

Operator Connect trades some of that flexibility for simplicity. Call routing is largely managed by the operator, with the Teams admin able to configure dialed-number translation but not the full routing stack, so the customization sits within what the operator profile allows.[1][7] For most standard calling needs that is enough, and keeping the routing with the operator is the point of choosing a managed model.[1][7] Organizations that need advanced routing logic, want to keep specialized on-premises equipment, or run their own contact-center integration tend to land on Direct Routing precisely because that control stays with them.[8][7]

Coverage and resilience are where the two models diverge in ways that are easy to miss during planning. Direct Routing is the only PSTN option that works in any country or region, because it depends on your carrier and SBC rather than on Microsoft or an operator selling service in that market.[1] Operator Connect is available only where a participating operator offers service, so a company with offices outside that footprint often combines connectivity types by region.[2]

Emergency calling and survivability also differ. With Operator Connect, the registered emergency address is optional and is enabled and managed by the operator, and dynamic emergency calling is supported.[1] Direct Routing supports dynamic location for emergency calls but requires additional configuration, and Microsoft's comparison notes that a registered, static emergency address is not supported the way it is for the managed options.[1] Direct Routing is also the only model that can keep local PSTN calls working through a Survivable Branch Appliance if the connection to the Microsoft cloud is interrupted, which matters for sites that cannot afford to lose dial tone during an outage.[1] United States deployments carry regulatory emergency-calling obligations under both models, so the address and routing setup deserves attention regardless of which you choose.[1]

The right model follows from your constraints rather than a ranking, since each is a good fit for a different situation. Operator Connect suits an organization that wants managed calling with little setup, whose preferred carrier is in the program or that is comfortable choosing a participating operator, especially where it does not need deep routing control.[2][1] Direct Routing suits an organization that needs a specific carrier, has to connect legacy PBX or analog equipment, wants full control of routing, or operates in a country where Operator Connect and Calling Plan are not sold.[1][3]

You can run both at once

A single tenant is not locked into one model. Microsoft supports mixing PSTN connectivity types, and you can even assign a user an Operator Connect or Calling Plan number while routing some of their calls, such as calls to a third-party PBX, through Direct Routing.[1][3] A frequent design uses Operator Connect for standard knowledge workers and Direct Routing for sites with legacy gear or carriers outside the program, which lets each office use the model that fits it.[1][9]

What to watch either way

Both models still require a Teams Phone license per user, so the connectivity choice sits on top of that cost rather than replacing it.[1][6] With Direct Routing, budget for the SBC and its upkeep, whether you run it or a provider does, because that infrastructure is the real difference in total effort.[3][10] With Operator Connect, confirm that an operator actually serves every country you need before you commit, since coverage is only as broad as the participating operators in your markets.[2]