---
title: "List a campaign's failed sends"
method: GET
path: "/api/v1/campaigns/{id}/failures"
tags: ["Campaigns"]
---

# List a campaign's failed sends

`GET /api/v1/campaigns/{id}/failures`

## Request

- Base URL: `https://api.sendly.now`
- URL: `https://api.sendly.now/api/v1/campaigns/{id}/failures`
- Auth: one of:
  - HTTP bearer
  - API key in cookie `better-auth.session_token`
  - OAuth 2 (authorization code, authorization URL `https://app.sendly.now/api/auth/oauth2/authorize`, token URL `https://app.sendly.now/api/auth/oauth2/token`, scopes: `campaigns:read`)

The recipients this campaign did not reach, read from its per-contact send ledger. The campaign counters say how many were sent; only this says WHO was dropped and why, which is what makes retrying a decision rather than a guess.

`reason` comes from a fixed vocabulary, not from the underlying error text, so it is stable enough to branch on. It is `null` for rows recorded before reasons were captured.

Cursor-paginated like every other v1 list. Unlike them it also returns `total`: the retry action operates on that number, and a page that can only say `has_more` cannot tell you whether 3 or 30,000 sends failed.

Requires the `campaigns:read` scope — View your campaigns and their performance.

## Path parameters

- `id` string, uuid, required: Resource id.

## Query parameters

- `limit` integer
- `after` string: Opaque cursor from a previous response's `next_cursor`.

## Response `200`

Failed sends

- CampaignV1FailureList: Cursor-paginated list of a campaign's failed sends.
  - `data` CampaignV1Failure[], required
    - `contact_id` string, uuid, required
    - `email` string, required: The recipient the send was for.
    - `failed_at` string, date-time, required
    - `id` string, uuid, required: Ledger row id. Pass the last one as `after` to page.
    - `reason` string, nullable, required
  - `has_more` boolean, required
  - `next_cursor` string, nullable, required: Pass as `after` to fetch the next page. `null` on the last page.
  - `total` integer, required: Every FAILED row on this campaign, not just this page.

## Other responses

- `401`: `invalid_api_key` or `invalid_session` — missing or invalid credentials.
- `403`: `scope_missing`, `project_access_denied`, or `project_disabled`.
- `404`: `resource_not_found` — no campaign with this id belongs to the authenticated project.
- `422`: `validation_error` — query, path, or body parameters did not match the schema.
- `429`: `rate_limited` — see `Retry-After` and the `RateLimit` headers.
- `500`: `internal_error`.

---

[API](https://skmtc.dev/sendly/apis/sendly-api.md) · [All operations](https://skmtc.dev/sendly/apis/sendly-api/llms.txt) · [OpenAPI document](https://skmtc.dev/sendly/apis/sendly-api/revisions/ce7cfb7f7c7e?raw)