E911 and Microsoft Teams: What You Must Configure

Why emergency calling is different in Teams

When someone dialed 911 from an old desk phone, the address came along automatically because the line was physically wired to a building. The phone couldn't be anywhere else.

Teams users move. The same account rings on a desk phone in the office, a laptop at home, and a cell phone on a train. If the system reports a fixed address for that user regardless of where they are, a 911 call from someone's apartment sends responders to your office. That's the problem every Teams deployment has to solve deliberately, because it does not solve itself.

The obligations, in plain terms

US regulations covering multi-line telephone systems set expectations that matter here. Broadly, they cover three things:

• Direct dialing. A user must be able to dial 911 without a prefix — no dialing 9 first.
• Dispatchable location. The emergency call should carry information specific enough to find the caller — not just a street address, but where in the building, for larger sites.
• Notification. Someone at the organization should be alerted when a 911 call is placed, so they can meet responders and direct them.

This is a compliance matter, not a nice-to-have, and the specifics can vary by state. If nobody on your side can say how your Teams deployment handles these, treat that as an open item rather than an assumption.

What has to be configured

Emergency addresses, validated

Every location where Teams users work needs a civic address entered and validated. Validation matters more than it sounds: an address your system accepts but the emergency network doesn't recognize will fail at the worst possible moment. Enter them, validate them, and fix the ones that don't validate rather than leaving them.

Places within a location

For anything larger than a single small office, a street address isn't enough. A twelve-story building with one address tells responders nothing about which floor. Teams supports defining places — floors, wings, suites — beneath an address, and that detail is what turns an address into a dispatchable location.

Network-based location

This is the part that makes location dynamic rather than static. You map network identifiers to addresses:

• Subnets — the simplest mapping, good for a single-address site
• Wi-Fi access points — by BSSID, which gets you floor-level accuracy in a larger building
• Ethernet switches and ports — the most precise, mapping a specific port to a specific place

When a device connects, Teams works out where it is from the network it's on, rather than from where the user was set up. That's what makes a user who moves between floors report accurately.

Emergency calling policies

These control notification. Decide who gets alerted when a 911 call is placed — typically reception, a security desk, or a facilities manager — and how they're alerted. Teams can notify by chat, and can optionally allow the notified person to listen in.

The value is practical: someone on site knowing a call went out is often what gets responders through a locked lobby to the right floor.

Emergency call routing policies

Required for Direct Routing deployments, where you control how emergency calls reach the emergency services provider. With Calling Plans or Operator Connect, more of this is handled for you — but confirm it rather than assume.

Remote and hybrid workers

The hardest case, and the one most often left unaddressed. Someone working from home is on a network you don't control and can't map.

Teams can prompt users to confirm or enter their location when it detects they're off the corporate network. That mechanism only works if two things are true: it's enabled, and your people know what it is. A user who dismisses an unexpected location prompt without reading it has just made their own 911 call less useful.

Tell people during onboarding. It takes one sentence: "If Teams asks you to confirm your address, it's for emergency calls — answer it accurately."

The mistakes we actually find

• One office address applied to everyone, including staff who work from home three days a week
• Addresses entered but never validated — they look fine in the admin center and fail in use
• No network mapping at all, so location is static no matter where the device is
• No security desk notification, meaning a 911 call happens and nobody on site knows
• Remote workers never told how location confirmation works
• New sites added later with nobody revisiting emergency configuration
• Common area phones in lobbies and warehouses left out of the location plan entirely

That last one is worth checking specifically. The lobby phone is exactly the device a visitor would grab in an emergency.

Testing it

You can and should verify emergency configuration — and there are ways to do it without tying up a dispatcher. Your provider or partner should know the current approach for your region and configuration. What matters is that someone has actually confirmed a test call carries the right address and triggers the right notification, rather than trusting the config screen.

Re-test after anything that changes the network: a new floor, a new office, a switch replacement, a Wi-Fi refresh.

Getting it right

Emergency calling is the part of a phone deployment where "we'll sort it later" carries real consequences. Callifi configures and verifies emergency calling as part of every Teams Phone deployment, including network mapping and security desk notification. For broader context on VoIP and 911 in New York, see 911 and VoIP for NYC businesses, or ask us to review your current setup.