---
title: workspace.locked_to_byoc
description: >-
  This workspace already uses its own SIP trunk and cannot buy numbers from
  Sautikit.
summary: >-
  Returned by number-claiming endpoints when the workspace has an active SIP
  trunk. The buy-or-bring choice is permanent per workspace — create a new
  workspace to buy a Sautikit number instead.
date: 2026-08-06T00:00:00.000Z
type: error
---


## Summary

`workspace.locked_to_byoc` means the workspace has already committed to bringing its own SIP trunk, so it cannot also buy numbers from Sautikit.

## Cause

Every workspace makes a one-time, permanent choice: buy numbers from Sautikit, or bring your own carrier trunk. The two paths are mutually exclusive — see [`workspace.locked_to_platform_numbers`](/developers/errors/workspace.locked_to_platform_numbers) for the reasoning.

The lock is set the moment your SIP trunk is **proven working** — a registration trunk that reaches `active`, or a signaling trunk Sautikit's operations team has approved — not merely when you submit one. A trunk that never registers leaves the workspace unlocked. Once locked, actions that buy a platform number (claiming from inventory) are refused.

## Resolution

If you want a Sautikit-provisioned number, create a new workspace for it — the lock is per workspace, not per account. If this workspace was locked to BYOC by mistake, disconnect the trunk first (`DELETE /v1/sip-trunk`, after releasing any BYO numbers on it — see [`sip_trunk.in_use`](/developers/errors/sip_trunk.in_use)) and ask support to reset the workspace's mode; there is no self-service way to reverse the lock once it is set.

## Example response

```json
{
  "error": {
    "code": "workspace.locked_to_byoc",
    "message": "this workspace uses its own SIP trunk, so numbers cannot be bought from Sautikit",
    "request_id": "req_01900000abc"
  }
}
```

## Next steps

- [Numbers concepts — the permanent buy-or-bring choice](/developers/concepts/numbers#bring-your-own-sip-trunk)
- [`workspace.locked_to_platform_numbers`](/developers/errors/workspace.locked_to_platform_numbers) — the mirror-image error on the other side of the same lock