---
title: "Changes to Send up to 100 emails"
method: POST
path: "/emails/batch"
---

# Changes to Send up to 100 emails

`POST /emails/batch`

> Every recorded change to this operation, newest first.

## Timeline

Changed in 4 of 7 revisions.

- **2026-11-12** `0d3971e3a670`: 5 warning
- **2026-10-27** `52b7a6be08b3`: 1 breaking, 2 info
- **2026-09-30** `4dc1e20989c8`: 12 warning, 1 info
- **2026-09-29** `ef5b22b98333`: 7 breaking, 5 warning, 11 info

## Changes

- **2026-11-12** `0d3971e3a670`: 5 warning
  - the `emails/items/bcc/items/` request property's maxLength was set to `320`
  - the `emails/items/cc/items/` request property's maxLength was set to `320`
  - the `emails/items/from` request property's maxLength was set to `998`
  - the `emails/items/reply_to` request property's maxLength was set to `320`
  - the `emails/items/to/items/` request property's maxLength was set to `320`
- **2026-10-27** `52b7a6be08b3`: 1 breaking, 2 info
  - the `emails/items/scheduled_at` request property type changed from `string` to no type, and format from `date-time` to no format
  - added `subschema #1, subschema #2` to the `emails/items/scheduled_at` request property `anyOf` list
  - removed the pattern `^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z))$` from the request property `emails/items/scheduled_at`
- **2026-09-30** `4dc1e20989c8`: 12 warning, 1 info
  - added the new `daily_limit_exceeded` enum value to the `anyOf[#/components/schemas/Error]/code` response property for the response status `403`
  - added the new `daily_limit_exceeded` enum value to the `code` response property for the response status `400`
  - added the new `daily_limit_exceeded` enum value to the `code` response property for the response status `401`
  - added the new `daily_limit_exceeded` enum value to the `code` response property for the response status `429`
  - added the new `monthly_limit_exceeded` enum value to the `anyOf[#/components/schemas/Error]/code` response property for the response status `403`
  - added the new `monthly_limit_exceeded` enum value to the `code` response property for the response status `400`
  - added the new `monthly_limit_exceeded` enum value to the `code` response property for the response status `401`
  - added the new `monthly_limit_exceeded` enum value to the `code` response property for the response status `429`
  - added the new `send_limit_exceeded` enum value to the `anyOf[#/components/schemas/Error]/code` response property for the response status `403`
  - added the new `send_limit_exceeded` enum value to the `code` response property for the response status `400`
  - added the new `send_limit_exceeded` enum value to the `code` response property for the response status `401`
  - added the new `send_limit_exceeded` enum value to the `code` response property for the response status `429`
  - added the optional property `data/items/oneOf[subschema #2]/code` to the response with the `202` status
- **2026-09-29** `ef5b22b98333`: 7 breaking, 5 warning, 11 info
  - the `emails/items/to` request property's minItems was increased to `1`
  - the `emails/items/attachments/items/content` request property's minLength was increased from `0` to `1`
  - the `emails/items/attachments/items/filename` request property's minLength was increased from `0` to `1`
  - the `emails/items/from` request property's minLength was increased from `0` to `1`
  - the `emails/items/subject` request property's minLength was increased from `0` to `1`
  - added the pattern `^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z))$` to the request property `emails/items/scheduled_at`
  - removed the success response with the status `200`
  - the `emails/items/attachments/items/content` request property's maxLength was set to `25000000`
  - the `emails/items/headers/additionalProperties/` request property's maxLength was set to `1024`
  - the `emails/items/idempotency_key` request property's maxLength was set to `64`
  - the `emails/items/subject` request property's maxLength was set to `998`
  - the `emails/items/tags/items/` request property's maxLength was set to `64`
  - added the new optional `header` request parameter `Idempotency-Key`
  - added the new optional request property `emails/items/attachments/items/content_id`
  - added the new optional request property `emails/items/idempotency_window_hours`
  - added the new optional request property `emails/items/signature`
  - added the new optional request property `emails/items/tracking`
  - added the new optional request property `emails/items/unsubscribe`
  - added the non-success response with the status `400`
  - added the non-success response with the status `401`
  - added the non-success response with the status `403`
  - added the non-success response with the status `429`
  - added the success response with the status `202`

---

[Operation](https://skmtc.dev/poststack/apis/poststack-api/docs/emails/batch/post.md) - [API](https://skmtc.dev/poststack/apis/poststack-api.md) - [Page](https://skmtc.dev/poststack/apis/poststack-api/changes/emails/batch/post)