v1

latestOpenAPI 3.1.0MIT2026-08-0652106151.4 KB

mail

Send email message

Servers

Host	Region
https://api.turbo-smtp.com/api/v2	Global (default)
https://api.eu.turbo-smtp.com/api/v2	European infrastructure — use for EU data residency

Notes:

- ConsumerKey / ConsumerSecret headers should be used. This endpoint does not support Authorization header

- Switch between samples to learn about advanced features such as using attachments, custom headers like reply-to address, tracking, embeded images and others.

Limitations:

The total size of your email, including attachments, must be less than 24MB.

post/mail/send

Request body

fromstring required

Sender information using either:

Email only format (user@example.com)
Display name with email (Name user@example.com)

tostring required

comma-separated recipients emails list

subjectstring nullable

email subject

ccstring nullable

comma-separated copy emails list

bccstring nullable

comma-separated hidden copy emails list

contentstring nullable

text content of the email

html_contentstring nullable

html content of the email

custom_headersobject nullable

email additional headers, use any additional header like standard ones List-Unsubscribe (to allow users to easily unsubscribe), X-Entity-Ref-ID (to handle how gmail and other clients group threads), and your own ones.

reference_idstring nullable

custom argument included within an email to be added to the Event Webhook response.

X-campaign-IDstring nullable

custom argument included within an email identify the campaign the email belongs to.

mime_rawstring nullable

mime message which replaces content and hmtl content

Example request

{
  "attachments": [
    {
      "content": "dXBsb2FkZXIxQGdtYWlsLmNvbQ0KdXBsb2FkZXIyQGdtYWlsLmNvbQ0KYWJjMQ==",
      "name": "email.ico",
      "type": "image/gif"
    }
  ]
}

Response

Sucess

Turbo-SMTP successfully received your message.

messagestring

midinteger

message ID

Example response

{
  "message": "OK",
  "mid": 1688566310828572700
}