E911 Dispatch Addresses

When someone dials 911 from a phone on your account, the upstream carrier needs to know where the caller is so emergency services can show up at the correct address. This page walks through how locations and devices fit together to make that work.

US federal law (Kari's Law and RAY BAUM's Act) makes the dispatch obligation strict: the address must be specific enough for first responders to find the caller, and dialing 911 must work without any prefix. DialStack handles the carrier side of that obligation; the account is responsible for keeping each device's location current as people move desks, branches, or sites.

The pieces

Two things combine to dispatch an emergency call:

• Locations — the physical sites your account operates from. Each location is a structured address registered with the upstream carrier. Manage them on the Locations page.

• Devices — the phones at those sites. The device placing the call is what determines the dispatch address:

  • Deskphone — its dispatch location is set on the device itself.
  • DECT base — its dispatch location is set on the base; every handset paired with the base inherits it.
  • DECT handset — has no location of its own; uses whatever the paired base has.

  Manage devices and their location assignment on the Devices page.

Only the calling device's location counts. The location of the phone number shown as caller ID, and the account's main location, play no part in where an emergency call is dispatched.

Softphone and in-app SDK calls are handled differently. There is no fixed physical site for these users, so the dispatch address comes from the user themselves rather than from a device's location. The app prompts each user to register an emergency address, validates it against the official street-address database, and re-prompts when the user's network changes (a typical signal they've moved offices, hotels, or home setups). Until the user has an address registered for their current network, the softphone can't place ordinary outside calls; 911 and the 933 test line always work. When that user dials 911, the call goes out with their currently-confirmed address attached — same dispatch quality as a fixed deskphone, as long as the user keeps up with the prompts.

Admins don't manage these addresses from the portal; each user owns their own. If the same user also has a deskphone or DECT handset assigned to them on the account, the two paths are independent — calls from the desk phone use the device's location, calls from the softphone use the user's registered address.

Provisioning a location

A new location is registered with the carrier from the Locations page, which shows each location's E911 status.

Only "Provisioned" locations actually dispatch. Assigning a device to a location that is still Pending or Binding, or has Failed, is allowed (handy during onboarding), but until the location is provisioned the platform sends no address for that device — see What happens at call time.

Assigning a device to a location

Every deskphone and DECT base always has a location. When you add one, the form includes a Location picker that defaults to the account's main location; pick the site the device actually lives at.

If no location is chosen — through the API, or on ordered hardware — the device gets a default: the account's only location, else the location of the user it's for, else the account's main location. You can move a device to a different location later from its detail page; clearing it puts it back on that default. Check the location of devices at secondary sites: a default is a guess, and a wrong one sends emergency services to the wrong address.

DECT handsets do not have a location field of their own — they inherit from the paired base. To change where a handset dispatches, either change the base's location (all handsets on that base follow) or re-pair the handset with a base at a different site, both from the device detail page. The handset's detail page shows the inherited location as read-only.

What happens at call time

1. The phone places the call.
2. The platform reads the location bound to that device (or the location of the paired base, for handsets).
3. If the location is Provisioned, the call carries that address and the carrier routes it to the emergency dispatch center for that address.
4. If the location is not yet provisioned, the 911 call still completes but no address is attached — the carrier routes it to a default dispatch center (typically tied to the calling number's area code), and the dispatcher who answers has no specific street address for the caller. They'll have to ask the caller verbally, which costs precious seconds in an emergency and only works if the caller is conscious and can speak.

Every 911 call also emails the account's emergency notification recipients, plus any recipients set on the calling location.

Outside calls are blocked until the location is provisioned

A deskphone or DECT handset whose location is not yet provisioned can't place ordinary outside calls. The caller hears an announcement that the phone has no registered emergency address, and the call ends. 911 and the 933 test line still go through, and calls to other extensions on the account are not affected. Outside calls work again as soon as the device's location is provisioned.

Keeping things accurate

• When a user moves desks within a site — no action needed, unless they also change devices. The device's location is what counts.
• When a user moves to a different office — reassign the device they take with them to the new location. If they switch to a phone that lives at the new office, no action needed: that phone already has its own location.
• When you swap out a phone — the replacement gets the location chosen when it was added (the main location unless you picked another). Check it on the device's detail page right after adding it.
• When you close a location — reassign the devices at that site first. A location that still has devices assigned to it can't be deleted (see Deleting a Location).

Failure modes to watch for

Situation	What happens at call time
Location is still Pending or Binding, or has Failed	911 completes, but no address is sent to the carrier: it routes to a default dispatch center with no street address for the dispatcher to act on. Ordinary outside calls are blocked.

Testing without dialing real 911

Do not place real 911 calls to test. Dial 933 instead — it's a non-routable test number that exercises the full dispatch flow and reads your registered address back to you, without contacting a real emergency dispatcher.