> ## Documentation Index
> Fetch the complete documentation index at: https://cntillion.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Existing Centillion Labs numbers

> Find existing managed numbers and get help with rentals and business verification

Existing phone numbers rented through Centillion Labs remain in your workspace.
Find them under **More → Channels → Phone** in the workspace sidebar. Assigned numbers
also appear on their agent's **Channels → Phone** page.

To connect a new number, [import it from your Twilio account or SIP
provider](https://cntillion.com/docs/channels/phone.md). For help with an existing Centillion Labs rental,
renewal, release or business verification, contact the Centillion Labs team.

## Assign an existing number

Open the number's row under **Phone Numbers** and choose its **Agent** in
**Phone number details**. You can also
open the original agent's **Channels → Phone** page, click **Add number** and
select an unassigned number. Assigning a number also turns on voice for the
agent if it was off.

A managed number stays with the agent it was purchased for. You can leave it
unassigned and attach it again to that original agent. It cannot move to a
different agent.

In number details, choose a published **Branch** or **Follow traffic split**
for incoming calls. **Outbound call** tests the original agent when the number
has an outbound connection. Normal calling permissions and charges apply.
See [phone tests and recent calls](https://cntillion.com/docs/channels/phone.md#send-a-test-call).

Owners and Members can change assignments. See [workspace
roles](https://cntillion.com/docs/workspaces/members.md).

## Rental and billing

Managed US local numbers cost USD 3 per number per month. Rental uses prepaid
workspace credits. Included plan credits and test credits cannot pay the rental.
Calls are charged separately using your workspace's
[credits](https://cntillion.com/docs/workspaces/billing.md).

Centillion Labs does not charge number rental for numbers in your own Twilio
account. Your provider's charges still apply, and calls through Centillion Labs
use workspace credits.

## Business verification

US carriers check who is calling. Before a managed number can place outbound
calls, Twilio reviews your business and registers your number for verified
caller ID. The number can receive calls while verification is pending.

Contact the Centillion Labs team to check verification progress, provide
business details or correct a submission. For outbound call setup, see
[Outbound AI calls](https://cntillion.com/docs/channels/outbound-calls.md).

## Release a number

Contact the Centillion Labs team to release a managed number or change its
renewal. Releasing stops calls to the number and returns it to Twilio, where
someone else may get it. Unassigning a number keeps the rental in your
workspace.

An agent with a managed number cannot be deleted until its numbers are released.


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