---
title: "Create Signup Billing Portal"
method: POST
path: "/api/v1/auth/signup/{session_id}/billing-portal"
tags: ["User APIs", "auth"]
---

# Create Signup Billing Portal

`POST /api/v1/auth/signup/{session_id}/billing-portal`

Create a Stripe Billing Portal session for a signup in payment_failed state.
The frontend should pass return_url that includes the signup session_id so
when the user returns from the portal they can poll GET /signup/{session_id}/status.

## Path parameters

- `session_id` string, required

## Request body

- SignupBillingPortalRequest — Request for creating a billing portal session during signup (e.g. to fix payment method).
  - `return_url` string, required — URL to return to after the portal (should include signup session_id for status polling)

## Response `200`

Successful Response

- SignupBillingPortalResponse — Response with Stripe Billing Portal URL for signup payment retry.
  - `url` string, required — Stripe Customer Portal URL
  - `session_id` string, required — Signup session_id (for frontend consistency)

## Other responses

- `422` — Validation Error

---

[API](https://skmtc.net/carbonarc/apis/carbon-arc-client-admin-api.md) · [All operations](https://skmtc.net/carbonarc/apis/carbon-arc-client-admin-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/carbonarc/carbon-arc-client-admin-api/revisions/a8ca30023371/schema)