Operator Connect vs Teams Direct Routing: Which PSTN Path Fits Your Organization?

Microsoft Teams supports three ways to add public-network calling to Teams Phone: Microsoft Calling Plans, Operator Connect, and Direct Routing. Calling Plans drop out of most enterprise evaluations early because they tie you to Microsoft as the carrier and Microsoft’s rates. The real decision is between Operator Connect and Teams Direct Routing, two very different ways to bridge Microsoft 365 to the rest of the phone network.

This guide walks through what each model actually is, where each one wins, the trade-offs in cost and control, a decision framework for picking between them, and why both models will continue to coexist (both inside individual Teams tenants and across the market as a whole). The goal is to help you reach a confident decision before you commit to a multi-year carrier or SBC contract.

What Is Operator Connect?

Operator Connect is Microsoft’s managed carrier program for Teams, launched in 2021. It works like a curated marketplace inside Teams Admin Center: Microsoft lists the approved operators in a given country, the customer picks one, signs a contract with that operator, and the carrier provisions Teams calling without the customer ever touching an SBC.

Behind the scenes the operator runs the SBC infrastructure, manages the TLS certificates, handles SIP OPTIONS monitoring, and is on the hook for the carrier connection. The customer experience reduces to assigning phone numbers to users from inside Teams Admin Center, with everything else handled by the operator’s network operations team. Microsoft documents the model in detail in its Operator Connect planning guide.

Two things make Operator Connect distinctive. First, the operator list is curated by Microsoft and varies by country: not every region has the same set of operators available, and some countries have only a handful. Second, the operator owns the customer relationship for the calling service, which means pricing, support, and SLAs all sit with the operator rather than Microsoft.

What Is Teams Direct Routing?

Direct Routing is the other path to a real phone number on Teams: the customer brings their own carrier and their own Session Border Controller, and Microsoft sees only the SBC’s FQDN. The SBC sits between the Teams cloud and the carrier’s SIP trunk, handling TLS termination, SRTP media encryption, and the SIP normalization Teams requires. Microsoft’s Direct Routing planning guide and certified SBC list set out the technical and certification requirements in full.

The model gives the customer side full control: any SIP-capable carrier, any country, any number of trunks, and a free hand at the SBC for routing rules, header manipulation, codec policy, and call recording. “Customer side” is the important caveat. Direct Routing is sometimes pictured as the model where the end customer’s own IT team racks an SBC, renews certificates, and runs the on-call rotation, but in practice that picture only really fits the very largest enterprises with a dedicated voice or network team. For everyone else, the SBC sits with someone the customer pays to run it: most often the MSP or service provider already delivering IT to that customer, sometimes a managed-SBC partner contracted specifically for the calling stack. We covered the technical SBC requirements in depth in the Teams Direct Routing learning page, so this article won’t repeat them.

That distinction is what makes Direct Routing the default for service providers and complex enterprises. One multi-tenant SBC can serve dozens to hundreds of customer Microsoft 365 tenants with isolated trunk groups and per-tenant routing, so the MSP runs the SBC operations once and the end customer never sees a certificate renewal. The same control surface that makes Direct Routing attractive to a multinational with strict recording requirements also makes it the natural delivery path for a 40-seat law firm whose MSP already runs the SBC anyway.

Side-by-Side Comparison

The table below covers the dimensions that usually drive the decision in practice. It deliberately goes beyond the basic “carrier choice / SBC required / flexibility” view, focusing on the operational and commercial differences that surface during evaluation.

None of these dimensions is inherently better; they describe different operating models. The right answer depends on which trade-offs match the organization that has to live with them.

When Operator Connect Is the Right Fit

Operator Connect works best when the organization buys calling directly from a carrier rather than as part of a managed-IT bundle, and is comfortable picking from the operator list Microsoft curates for its country. The clearest fits share that buying pattern.

Mid-market and enterprise organizations that source telecom directly from a national carrier are the most natural fit. The organization already deals with the carrier for mobile, MPLS, or fixed lines; Operator Connect lets that same carrier add Teams calling without introducing a new vendor relationship. The carrier owns the SBC, the certificates, and the SLA, and the customer’s IT team adds Teams calling to a roster of carrier-managed services rather than to a list of things they now operate.

Teams-only environments where every user is on Microsoft 365 and no on-premises PBX or legacy contact center is in scope are a strong fit. The operator’s managed model removes the moving parts that Direct Routing introduces and that those environments do not actually need.

Organizations that prefer one bill and one SLA often pick Operator Connect specifically because it consolidates the calling stack into a single vendor relationship. Procurement, finance, and support all benefit from the simpler accountability model when the question “who do I call when calls are broken?” has only one answer.

Greenfield Teams deployments at organizations without an existing MSP relationship for voice are another clean fit. With no MSP already running an SBC on their behalf, the choice is between Operator Connect or sourcing Direct Routing for the first time. Operator Connect treats calling as a managed service from day one, which is the path of least resistance when nothing about the existing stack pulls toward an SBC.

When Teams Direct Routing Is the Right Fit

Direct Routing earns its keep when an MSP is in the picture, when carrier or geography choice matters, or when SBC-level control is required. Several patterns come up repeatedly in customer evaluations.

MSPs and service providers delivering Teams calling to a portfolio of customers is the dominant pattern, and the one that makes Direct Routing the right answer for far more end customers than the framing of “customer-managed SBC” suggests. A single multi-tenant SBC can serve dozens to hundreds of customer Microsoft 365 tenants with isolated trunk groups, which is structurally not what Operator Connect is built to do. Teams Direct Routing has been the #1 purchase trigger for North American MSPs in recent ProSBC sales calls, which tracks with the structural fit. The companion SBC for MSPs guide covers this in more depth.

Small and mid-size businesses already buying IT from an MSP are the second-order beneficiary of that pattern, and the segment most often misread in OC-vs-DR comparisons. These businesses do not have an internal team capable of running an SBC, and they never will. What they do have is a managed-services partner already running one on a multi-tenant platform. Adding Teams calling to the customer’s IT bundle means the MSP provisions another isolated tenant on the SBC they already operate; the customer pays the MSP, sees a single invoice for IT and calling, and never touches the SBC. From the customer’s chair this looks more like a managed service than Operator Connect’s per-user calling plan does, because the MSP also handles email, security, endpoints, and helpdesk in the same bundle.

Existing carrier relationships at negotiated rates are the next most common driver. An organization that has spent years getting to favourable per-minute pricing with a specific carrier rarely wants to surrender that contract to an operator. Direct Routing keeps the carrier in place and pays for the SBC separately.

Multi-country footprints push organizations toward Direct Routing when no single Operator Connect operator covers every region they need. Stitching together three or four operators in different countries through one Teams tenant is workable, but the operational simplicity that Operator Connect promises starts to evaporate once the operator list fragments.

Compliance-driven workloads are a structural fit for Direct Routing. Call recording for regulated industries, lawful intercept where mandated by law, and strict data-residency requirements are all handled cleanly at the SBC layer, where the customer controls the configuration. Operator Connect handles whatever the operator chooses to expose, which is rarely a fit for highly regulated environments.

Contact centers, BPOs, and enterprises with non-trivial SIP requirements (header manipulation for legacy carrier quirks, hybrid coexistence with an on-premises PBX during migration, custom codec policy, or call routing logic that involves CRM or fraud-detection lookups) need the SBC as the place where those rules live. Operator Connect does not give the customer that surface.

Very large enterprises with an internal voice or network team are the one segment that actually fits the “customer runs the SBC in-house” picture sometimes attached to Direct Routing. Multinationals, large financial institutions, and federal-scale agencies have the headcount and the operational maturity to take that on directly. They are the minority of Direct Routing customers in absolute terms, but they are the segment where the in-house operating model is real.

The Cost and Control Trade-Off

The cleanest way to think about Operator Connect versus Direct Routing on cost is as predictability versus negotiability rather than as expensive versus cheap.

Operator Connect’s pricing is typically per user per month, bundled into the operator’s calling plan. There is one number on the invoice. The pricing is predictable, which finance teams appreciate, and the operator absorbs the cost of the SBC, the certificates, and the on-call team behind the scenes. The catch is that the unit price reflects all of that bundled in, and the customer does not get to negotiate the SBC infrastructure or the carrier minutes as separate line items.

Direct Routing splits the same total cost into negotiable parts. The SBC license is one line (software SBCs start from about $1.25 per session per year on the low end of the market), the carrier provides minutes on its own commercial terms, and any managed-service partner handling SBC operations bills separately. Each line item is leverage. The cost goes down at scale, which is exactly why MSPs deliver Direct Routing across a portfolio of customers from a single multi-tenant SBC: the per-customer SBC cost falls toward zero as the tenant count rises. For end customers buying through an MSP, the line-item complexity stays on the MSP’s side; the customer sees a single bundle price.

The honest summary of the trade-off is that Direct Routing’s true cost includes SBC operations: certificate management (the June 2026 CA root update is a recent example), monitoring, security hardening, and failover testing. Those costs do not vanish; they sit with whoever runs the SBC. For most end customers, that is the MSP or managed-SBC partner already in the picture, and the operating cost is folded into the partner’s bundled fee. Only at the very largest enterprises with internal voice teams does the operating cost land on the customer’s own ledger.

Why Operator Connect and Direct Routing Coexist

Coexistence between the two models is not a stopgap. It happens at two levels that are easy to confuse: inside a single Teams tenant, and across the market as a whole.

Inside one Teams tenant, Microsoft supports Operator Connect and Direct Routing simultaneously, and number assignment is per user, so different users in the same organization can be on different models. The pattern that emerges in practice looks something like this: Operator Connect covers headquarters and the regions where a single approved operator already provides excellent service, and Direct Routing covers everything else (the contact center, the country where no Operator Connect operator is available, the legacy PBX still being decommissioned, the regulated business unit that needs SBC-level recording). The IT team gets the simplicity of Operator Connect where simplicity is achievable, without forcing it on parts of the organization where it does not fit. This hybrid pattern is one of the more underappreciated options in the evaluation.

Across the market, the same idea plays out at a much larger scale, and it explains why neither model is going to displace the other. Operator Connect and Direct Routing serve two different distribution channels, and Teams calling needs both channels to reach every kind of customer.

Operator Connect rides the direct-from-carrier channel. The customer signs a contract with a national carrier the same way they would for any other voice service, and the carrier takes responsibility for the SBC and the connectivity. That channel works for organizations large enough to deal directly with a carrier, in countries where the operator list covers what they need.

Direct Routing rides the MSP and service-provider channel. A managed-services partner already runs a multi-tenant SBC for a portfolio of customers, and Teams calling is one more service the partner adds to the bundle. Most small and mid-size businesses do not have an internal IT team large enough to run an SBC, and they do not need one: their MSP is already running one for them, alongside email, security, endpoints, and helpdesk. The customer experience is “the MSP added Teams calling to our service,” with no SBC on the customer’s side at all.

For Teams calling to be deliverable to every kind of buyer (from a 12-person law firm buying everything from a local MSP, to a multinational with an internal voice team, to a national contact center with strict recording requirements), both channels need to exist, and both will continue to exist. Operator Connect and Direct Routing are not competing models pulling at the same buyer. They are parallel distribution paths into different parts of the market, and the long-term equilibrium is both, not one.

Frequently Asked Questions

Conclusion

Operator Connect and Teams Direct Routing solve the same problem (PSTN calling on Teams) in fundamentally different ways, and they reach the buyer through fundamentally different channels. Operator Connect offers managed simplicity inside a curated operator list, sold to the customer directly by a national carrier. Direct Routing offers control over carrier, SBC, and routing, delivered most often by an MSP running a multi-tenant SBC across a portfolio of customers, sometimes by a managed-SBC partner, and only at the very largest enterprises in-house.

The honest decision framework is to start with how the organization buys IT, then layer on the technical requirements. If the customer sources telecom directly from a national carrier and that carrier is on the approved operator list, Operator Connect is the path of least resistance. If the customer already buys IT from an MSP, the MSP’s existing SBC is almost always the path of least resistance too, and the resulting model is Direct Routing whether the customer thinks of it that way or not. If the technical requirements pull toward compliance, multi-country coverage, or non-trivial SIP work, Direct Routing is the only model that exposes the SBC control surface those requirements need. Running both in the same tenant is supported and is often the calmest answer for organizations whose footprint genuinely spans both worlds.