---
title: "Refer call"
method: POST
path: "/realtime/calls/{call_id}/refer"
tags: ["Realtime"]
---

# Refer call

`POST /realtime/calls/{call_id}/refer`

Transfer an active SIP call to a new destination using the SIP REFER verb.

## Path parameters

- `call_id` string, required

## Request body

- RealtimeCallReferRequest — Parameters required to transfer a SIP call to a new destination using the Realtime API.
  - `target_uri` string, required — URI that should appear in the SIP Refer-To header. Supports values like `tel:+14155550123` or `sip:agent@example.com`.

## Response `200`

Call referred successfully.

## Other responses

- `404` — The session or call was not found or is unavailable for this operation.
- `500` — An internal error occurred. The response body is plain text.

## Changes

- **2026-09-25** `d86203de41ae` — 2 info
  - added the non-success response with the status `404`
  - added the non-success response with the status `500`
- **2026-05-13** `74cbcf73838f` — 1 info
  - endpoint added

[Change history](https://skmtc.dev/openai/apis/openapi/changes/realtime/calls/:call_id/refer/post.md)

---

[API](https://skmtc.dev/openai/apis/openapi.md) · [All operations](https://skmtc.dev/openai/apis/openapi/llms.txt) · [OpenAPI document](https://skmtc.dev/openai/apis/openapi/revisions/d86203de41ae?raw)