---
title: "Update A2P Registration"
method: PATCH
path: "/v1/register"
tags: ["registration"]
---

# Update A2P Registration

`PATCH /v1/register`

Update an existing A2P 10DLC registration.

Send only the fields that changed — everything is optional. There is no
fee. Changes are applied after review, and your registration keeps
sending under its current approval while an update to an approved
registration is reviewed.

Registrations created with create_sub_account=true (the default) live on
a sub-account; this resolves to it automatically when there's exactly
one, or honors the X-Sub-Account-Id header.

## Request body

- RegistrationUpdateRequest — Partial update to an existing registration. Every field is optional; provide only what changed. No fee — updates go through review before taking effect.
  - `business_name` string, nullable — Legal/registered business name.
  - `brand_name` string, nullable — Public-facing brand name if different from business_name.
  - `website_url` string, nullable
  - `description` string, nullable — What your business does, who you message, and what types of messages you send. Min 40 chars.
  - `use_cases` UseCase[], nullable — 1-5 specific use cases for your SMS campaign.
  - `volume` 'low' | 'high'
  - `message_samples` string[], nullable — 2-5 example messages. Each must be 20-1024 chars and include your brand name.
  - `consent_flow` string, nullable — How users opt in to receive messages. Min 40 chars.
  - `privacy_policy_url` string, nullable
  - `terms_of_service_url` string, nullable
  - `opt_in_image_url` string, nullable — Publicly accessible URL to a screenshot of your opt-in flow (PNG, JPG, WEBP, or GIF, max 2MB)
  - `includes` CampaignInclude[], nullable — Content types included in messages.
  - `link_sample` string, nullable — Example URL if messages contain links.

## Response `200`

Successful Response

- RegistrationUpdateResponse
  - `ok` boolean, required
  - `message` string, required
  - `campaign_status` string, required
  - `updated_fields` string[], required
  - `sub_account_id` string, nullable — Set when the update was applied to a registration on a sub-account of the calling account (the default for POST /v1/register).

## Other responses

- `422` — Validation Error

---

[API](https://skmtc.net/agentphone/apis/agentphone-api.md) · [All operations](https://skmtc.net/agentphone/apis/agentphone-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/agentphone/agentphone-api/revisions/3b532aaaf51c/schema)