---
title: "Add Emails to Suppression List"
method: POST
path: "/v1/batch/suppression-lists/{listId}/emails"
tags: ["Cost Control"]
---

# Add Emails to Suppression List

`POST /v1/batch/suppression-lists/{listId}/emails`

Add emails to an existing suppression list. Emails are SHA-256 hashed server-side.

## Path parameters

- `listId` string, required

## Request body

- object
  - `emails` string[], required

## Response `200`

Emails added.

## Other responses

- `400` — Bad Request - The request was malformed or contains invalid parameters. **Common causes:** - Missing required fields - Invalid field format (e.g., malformed email) - Invalid JSON syntax - Invalid parameter values
- `401` — Unauthorized - Authentication failed. **Common causes:** - Missing X-API-Key header - Invalid or expired API key - Malformed API key

---

[API](https://skmtc.net/leadmagic/apis/leadmagic-api.md) · [All operations](https://skmtc.net/leadmagic/apis/leadmagic-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/leadmagic/leadmagic-api/revisions/aa19cf9bc46a/schema)