What registration covers
Two separate mechanisms decide how your number appears on a US or Canadian recipient's phone.
| Mechanism | What it controls | Who does it |
|---|---|---|
| STIR/SHAKEN | Cryptographic attestation that the caller ID is legitimate | Handled by Finn automatically on Finn-provisioned numbers |
| CNAM | The business-name text displayed next to the number | You submit, carriers approve |
Neither one guarantees a clean label. Carriers weigh several other signals, including call volume, answer rate, and spam reports. See spam labeling for the full set.
STIR/SHAKEN attestation
The originating carrier signs each outbound call. The terminating carrier verifies the signature and decides whether to trust the caller ID.
| Level | Meaning | Practical effect |
|---|---|---|
| A (Full) | Caller ID verified as the number in use, and the originator is a known customer of the carrier | Best label outcomes |
| B (Partial) | Origin known, caller ID not fully verified | Mixed |
| C (Gateway) | Call entered from outside the carrier's verified network | Often spam-labeled regardless of call content |
Every call originated from a Finn-provisioned number is A-level attested by default. There is nothing to configure and nothing to submit.
Where this breaks. If you bring your own number over a SIP trunk, attestation is produced by your carrier, not by Finn. If that carrier signs at C-level, or does not sign at all, your calls carry that attestation into the network and Finn cannot upgrade it. Confirm A-level outbound signing with your SIP provider before you launch. See BYO numbers and BYOC SIP.
CNAM registration
Without CNAM, the recipient sees generic text: "Unknown Caller", "Wireless Caller", or bare area-code information. With it, they see your business name.
Registration is done in the dashboard. There is no API endpoint for it.
- Go to Settings → Phone numbers → [Your Number] → Caller ID Registration.
- Submit these fields:
| Field | Notes |
|---|---|
| Legal business name | Must be the registered entity name, not a trading name you prefer |
| EIN (US tax ID) or equivalent | |
| Business address | |
| Phone number | The number being registered |
| Expected monthly call volume | |
| Use case description | Specific descriptions pass. Vague ones get rejected |
A usable use case reads like "B2B sales follow-up calls to leads who filled out our website form." A description that does not say who you are calling or why is a common rejection cause.
- Submit and wait. Approval takes 1 to 3 weeks.
During that window your calls are still A-level attested, because attestation is independent of CNAM. The displayed label stays generic until carriers approve.
Sequence this before your campaign
Buying a number takes about a minute. Registration takes weeks. If you provision numbers the day before a campaign launches, you will run that campaign unregistered, and unregistered high-volume outbound gets labeled. Register at the point you buy, not at the point you dial. See phone numbers.
The same applies to number pools. Registration is per number. Adding ten numbers to a pool means ten registrations, each on its own approval clock.
What registration does not fix
Registration is a floor, not a ceiling. Numbers that are correctly registered still get labeled when other signals go bad:
- Sustained answer rate below roughly 15% causes carriers to treat the number as a spam source. The effect is self-reinforcing, since labeling lowers answer rate further.
- High call volume from a newly provisioned number reads as suspicious on its own.
- Recipient spam reports carry weight regardless of what your CNAM record says.
If you are already registered and still being labeled, the fix is in campaign behaviour, not in resubmitting the form. See spam labeling and outbound campaigns.
Outside the US and Canada
CNAM and STIR/SHAKEN are US and Canadian mechanisms. Other countries have their own gate. Calling Indian numbers requires DLT registration, submitted under Settings → Phone numbers → India DLT Registration, with approval typically in 3 to 5 business days. Regulated countries may also require KYC or business verification before a number is provisioned at all.
Check per-country requirements in compliance regions before you assume a number is dialable.
Checking status
Registration and compliance state per number is visible under Settings → Phone numbers → [Number] → Compliance Status. If outbound calls to one country fail while another country works, that screen is the first thing to read. A "carrier rejected" failure on outbound usually means the from-number is either unregistered for the destination country or not attested.