---
title: "Add people to a manual segment"
method: POST
path: "/api/v1/segments/{segment_id}/add_customers"
tags: ["Track Segments"]
---

# Add people to a manual segment

`POST /api/v1/segments/{segment_id}/add_customers`

Add people to a manual segment by ID. You are limited to 1000 customer IDs per request.

This endpoint lets you add people to manual segments, but a segment must exist before you can add people to it. You can create and find manual segments using the [App API](/integrations/api/app/tag/segments/createManSegment/).

When you call this API, you can pass an `id_type` query parameter determining the type of identifier you want to use, `id`, `email`, or `cio_id`; If you don't pass this parameter, it defaults to `id`. The request body always uses `ids`, even though it'll accept either IDs, emails, or `cio_id`s depending on the query parameter. Everybody in the payload must use the same kind of identifier; we'll ignore values in the `ids` array that don't match the `id_type` parameter.

**NOTE**: You cannot add people to data-driven segments using the API. See [our documentation on segments](/journeys/segmentation/segments) for more information about segments.

## Request body

- object — The IDs of people you want to add to the segment.
  - `ids` string[], required — The customer IDs you want to add to the segment. The type of value you pass in the array corresponds to the `id_type` query parameter—`id`, `email`, or `cio_id`. Entries in the array that don't match the `id_type` are ignored.

## Response `200`

A successful request returns an empty object response.

## Other responses

- `400` — Invalid or malformed request.
- `401` — Unauthorized request. Make sure that you provided the right credentials.

---

[API](https://skmtc.dev/customer/apis/customer-io-journeys-api-reference.md) · [All operations](https://skmtc.dev/customer/apis/customer-io-journeys-api-reference/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/customer/customer-io-journeys-api-reference/revisions/4b391af7cb06/schema)