Caller IDs
A caller ID is a number your workspace can present on an outbound call. Bird checks the SIP From header on every call against the Bird numbers this workspace can present and its verified external numbers. Calls that present an ineligible number are refused.
Manage caller IDs under Voice > Numbers, which lists every number your workspace can use for voice. A number you bought from us and a number you verified appear in the same list, one row per number. A number that is both appears once. A number you bought from us is ready to present as soon as you hold it, with no verification call: holding it is the proof. The procedure below is for a number you own somewhere else.
Each row shows the name, the number and its country, its Provider, the directions it carries, and what it is used for. A number awaiting its code shows Verifying; one whose code expired or attempts ran out shows Failed. Each page contains up to 25 numbers. Select a row to open that number's own page.
Register a number
- Select Add number > Verify a number you own.
- Enter the number in E.164 format: a leading +, country code, and national number. A number can be registered once in your workspace.
- Save it. A verification call is placed to the number straight away.
- Answer the call and listen for the six-digit code.
- Enter the code in the dashboard. You have five attempts, and an accepted code changes the status to Verified.
Caller-ID verification does not charge your workspace for the verification call. Registration still requires Voice management permission and the account's approval to register verified numbers. Name the number afterwards on its own page. See Name a number.
After verification, check the country you intend to call under Voice > Destinations. Verification attempts to enable the verified number's country, but unavailable countries or a failed settings update can leave it disabled. A verified caller ID and an enabled destination are separate requirements.
Complete verification through the API
After registering a number in the dashboard, list your caller IDs to find its ID, then submit the code. Reads require voice_management:read; verification requires voice_management:write. The API reference includes SDK, Bird command-line, and MCP examples.
If the original verification call could not be started, submitting the code can start another call to the registered number. Your organization must still meet the registration requirements. If the code expires or attempts are exhausted, return to Voice > Numbers and select Get a new code. This action removes the registration and registers the number again. List caller IDs again to find the new registration's ID before submitting its code. Registration and deletion remain dashboard operations.
After verification, check your Voice destinations and enable the number's country when supported and needed. Verification attempts to enable it, but a successful caller-ID verification can leave the destination disabled and outbound calls to that country blocked.
One verification at a time
Registration can return E21036 when the verification provider already has a challenge for that number belonging to another workspace or purpose. Wait for that verification to finish or expire, then register the number again. A proof obtained for another workspace does not verify the number in yours.
The same refusal covers a number that is busy for another reason: a login code or a Trust Hub verification already in flight to it. If no other workspace is verifying the number, that is usually why, and the wait is the same.
A verification that has already finished elsewhere does not block you: the same number can be a verified caller ID in more than one workspace, and each one proves it separately.
Statuses
| Status | What it means |
|---|---|
| Pending | Registered, awaiting the code. Use Enter code on the row to finish it |
| Verified | The code was accepted. The number can be presented as the caller on outbound calls |
| Failed | The code expired or attempts were used up. Use Get a new code on the row for a fresh verification call |
Get a new code registers the number again and calls it with a new code. If the first call never arrived and the number is still pending, remove the caller ID and add the number again.
If you read these values from your own tooling, match the ones you handle and treat any other as a status you do not handle rather than an error.
CLI verification and delivery disclaimer
Bird performs CLI (Calling Line Identification) verification to confirm that an A-number is valid and authorised for use before outbound calls can be placed from the platform. This verification ensures the number is legitimate and under the customer's control.
However, verification does not guarantee end-to-end delivery of the CLI or connection of the call where the CLI is not a number procured through Bird. Downstream carriers and international operators apply their own national regulations and traffic policies, which are outside Bird's control. These may include:
- Anti-spoofing and caller ID authentication frameworks (e.g. STIR/SHAKEN in the US, Ofcom CLI guidelines in the UK)
- Requirements for the CLI to be a locally registered or in-country number
- Spam and fraud filtering applied by terminating operators
- Restrictions on specific traffic categories, such as gambling, financial promotions, debt collection, or political messaging
- Blocking of international calls presenting a domestic CLI ("origin-based" restrictions)
- Do-not-originate lists and regulator-mandated blocking
For these reasons, Bird can verify a CLI but cannot guarantee that (1) the CLI will be preserved and displayed to the called party, or (2) the call will connect via domestic trunks or international Tier 1 partners and operators. To maximise CLI delivery and call completion rates, we recommend using numbers procured through Bird, which are provisioned and routed in line with local regulatory requirements.
Name a number
A name labels the number in the dashboard and in the dialer's Call from list. It is not sent with the call.
Select the number in the Numbers list to open its page, then set Name and save. Leave the field empty to show just the number. Naming works at any status and does not change the number or its verification.
Verify a number you cannot answer
Someone must answer the verification call and hear its code. If the number normally reaches an unattended system, route it temporarily to a phone you can answer, then move it back. Contact support if the number cannot receive calls.
Remove a caller ID
Use Remove caller ID on the number's row. Removing verification takes away that proof for new calls. A number held by your workspace through Bird can remain eligible through its allocation; an external number that loses its proof is refused with caller_id_not_verified. Calls already in progress continue, and existing call records do not change.
Next steps
| Page | What it covers |
|---|---|
| Placing calls | What Bird expects on the INVITE, including the From header |
| SIP trunks | Creating a trunk and controlling which addresses and keys may use it |
Related resources
Continue with the documentation, guides and examples for this topic. Resources are in English.
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