---
title: "Connect a Slack channel"
method: POST
path: "/v1/connect/slack"
tags: ["Connect"]
---

# Connect a Slack channel

`POST /v1/connect/slack`

Finalize a Slack connect by creating the per-channel account. Served by a dedicated route, so it is not reachable through POST /v1/connect/{platform}. Send pendingDataToken for a first connect (the nonce from the OAuth redirect) or accountId to add another channel to a workspace already connected.

## Request body

- object
  - `profileId` string, required
  - `channelId` string, required — Slack channel id, C... or G...
  - `pendingDataToken` string — Nonce from the OAuth redirect. Required unless accountId is sent.
  - `accountId` string — Existing Slack account whose workspace token is reused. Required unless pendingDataToken is sent.

## Response `200`

Channel connected

## Other responses

- `400` — Invalid request
- `401` — Unauthorized
- `402` — Payment method or enterprise contract required. The authenticated account hit a billing gate before the connection could proceed. Three reasons: - `free_tier_exceeded`: the team has connected more accounts than the free tier allows. Add a payment method on the dashboard to continue (the user will be billed per additional connected account). - `twitter_passthrough`: connecting an X (Twitter) account requires a card on file from day one because X API calls incur real per-call pass-through costs. Applies to the 1st X account, not just the 3rd+. - `enterprise_required`: the team is on an enterprise contract with a negotiated connected-account cap and has reached it. Self-service teams have NO connection cap (the $1/account rate continues at any scale), so this reason can only fire for teams whose contract sets an explicit limit. `dashboard_url` deep-links to the enterprise contact page rather than the billing tab. The end-user already has a card on file; this gate is about contract terms, not card collection. SDK consumers should switch on `reason` to render the right prompt. For `free_tier_exceeded` and `twitter_passthrough`, redirect the end-user to `dashboard_url` to add a payment method via Zernio's hosted Stripe Setup Checkout. For `enterprise_required`, redirect to `dashboard_url` (the enterprise contact form) to adjust the contract's limit.
- `403` — Slack connections are temporarily unavailable
- `404` — Profile not found

## Changes

- **2026-08-25** `44b6b1ca2a8b` — 1 info
  - endpoint added

[Change history](https://skmtc.dev/zernio/apis/zernio-api/changes/v1/connect/slack/post.md)

---

[API](https://skmtc.dev/zernio/apis/zernio-api.md) · [All operations](https://skmtc.dev/zernio/apis/zernio-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/zernio/zernio-api/revisions/bdd771244d76/schema)