The same call can display one name on one phone and a different name on another. The caller chose neither of them for that call. That is possible because the number and the name reach a handset by different routes, decided by different parties.

## What does the call itself carry?

A number, and a claim about who is entitled to use it.

The calling number is part of the call setup. It arrives with the call. It is the thing a receiving network can act on immediately. What does not arrive is a name.

Signing changes the strength of the number, not the presence of a name. [STIR/SHAKEN](/explained/voice/what-is-stir-shaken) attests that the caller is entitled to use the calling number, which is a statement about the number and nothing else. A perfectly attested call still displays whatever name the receiving side decides to show.

## Where does the name come from?

A database the receiving carrier queries, keyed on the number.

CNAM, the calling name service, is a lookup performed at the terminating end. The receiving carrier takes the calling number, asks a calling-name database what name is on record for it, and passes the answer to the handset. The caller is not consulted.

Two consequences follow. Because the lookup happens at the far end, different carriers can show different names for the same call. A stale record keeps showing an old name long after a business changes it. Because the caller is not consulted, no setting on your side determines the result.

## What actually decides the name on the screen?

One of four things. They take precedence in roughly this order.

| Source                    | Where it comes from                                   | What it means for you                                      |
| ------------------------- | ----------------------------------------------------- | ---------------------------------------------------------- |
| A saved contact           | The recipient's own address book                      | You cannot influence it, and it usually wins               |
| A CNAM record             | A calling-name database the receiving carrier queries | Changed through whoever holds the record for the number    |
| A spam label              | The receiving carrier's or handset's own analytics    | A judgment about the traffic, not a name at all            |
| An authenticated identity | A signed call, verified at the receiving end          | Establishes the number is legitimately yours, not the name |

A recipient who has the number saved sees their own label whatever anyone else does. A call scored as unwanted can display a warning in place of any name. [Why a call is labeled spam likely](/explained/voice/why-is-my-call-labeled-spam-likely) covers the last row.

## Is setting a display name the same as proving a number is mine?

No. They are separate problems with separate mechanisms.

Proving control of a number is done by verifying it, which earns you the right to originate calls from it. Publishing a name for a number is done by updating a calling-name record, through the party that holds it.

A provider can do the first without doing the second. The first is a relationship with your own carrier. The second is a record in a database queried by everyone else's.

## What can I do on Bird?

Register and verify a number you already hold. Treat the name as a local label.

Bird verifies an externally held number by placing a call to it and asking for a code, which establishes that you control the number well enough to originate calls from it. The [caller IDs guide](/docs/guides/voice/caller-ids) covers that flow, which runs from the dashboard rather than the public API.

The `name` on a registered caller ID is your own label for telling several registered numbers apart. It appears nowhere on a call, so changing it never affects what the person you are calling sees. Nothing on Bird publishes a calling name. Plan a display-name change with whoever holds the CNAM record for the number.

## Related resources

- [SMS numbers](/products/sms/numbers) (product)
- [Number types](/docs/guides/numbers/number-types) (docs)
- [What is a virtual phone number (VMN)?](/explained/numbers/what-is-a-virtual-phone-number) (answer)

[Get an implementation brief](/learn/workspace?topic=phone-numbers)