> For the complete documentation index, see [llms.txt](https://docs.mailtrap.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mailtrap.io/developers/email-sending/transactional/send-transactional-email.md).

# Send transactional email

Send a single transactional email with text, HTML, or template content.

Use this endpoint for:

* Order confirmations
* Password reset emails
* Account notifications
* Welcome emails
* System alerts

```json
{"openapi":"3.1.0","info":{"title":"Transactional","version":"2.0.0"},"tags":[{"name":"send-email","description":"Send transactional emails for order confirmations, password resets, and notifications.\n\n{% hint style=\"success\" %}\nBest for: Real-time, one-to-one emails triggered by user actions\n{% endhint %}\n"}],"servers":[{"description":"Transactional Stream. Use a normal HTTP client `User-Agent` (as typical browsers and `curl` do); bare\nrequests without one may be blocked by edge protection.\n","url":"https://send.api.mailtrap.io"}],"security":[{"HeaderAuth":[]},{"BearerAuth":[]}],"components":{"securitySchemes":{"HeaderAuth":{"type":"apiKey","description":"API token in Api-Token header","in":"header","name":"Api-Token"},"BearerAuth":{"type":"http","scheme":"bearer","bearerFormat":"JWT","description":"Bearer token authentication"}},"schemas":{"EmailWithText":{"title":"Text Only","allOf":[{"$ref":"#/components/schemas/EmailSenderRequired"},{"$ref":"#/components/schemas/EmailRecipients"},{"$ref":"#/components/schemas/EmailReplyTo"},{"$ref":"#/components/schemas/EmailSubjectRequired"},{"$ref":"#/components/schemas/EmailTextRequired"},{"$ref":"#/components/schemas/EmailAttachments"},{"$ref":"#/components/schemas/EmailSendingHeaders"},{"$ref":"#/components/schemas/EmailCustomVariables"},{"$ref":"#/components/schemas/EmailCategory"}]},"EmailSenderRequired":{"type":"object","required":["from"],"properties":{"from":{"$ref":"#/components/schemas/Address"}}},"Address":{"type":"object","properties":{"email":{"type":"string","format":"email"},"name":{"type":"string"}}},"EmailRecipients":{"type":"object","properties":{"to":{"type":"array","maxItems":1000,"items":{"$ref":"#/components/schemas/Address"}},"cc":{"type":"array","maxItems":1000,"items":{"$ref":"#/components/schemas/Address"}},"bcc":{"type":"array","maxItems":1000,"items":{"$ref":"#/components/schemas/Address"}}}},"EmailReplyTo":{"type":"object","properties":{"reply_to":{"$ref":"#/components/schemas/Address"}}},"EmailSubjectRequired":{"type":"object","required":["subject"],"properties":{"subject":{"type":"string","minLength":1}}},"EmailTextRequired":{"type":"object","required":["text"],"properties":{"text":{"type":"string","minLength":1}}},"EmailAttachments":{"type":"object","properties":{"attachments":{"type":"array","items":{"type":"object","required":["content","filename"],"properties":{"content":{"type":"string","description":"Base64 encoded content"},"filename":{"type":"string"},"type":{"type":"string","description":"MIME type"},"disposition":{"type":"string","enum":["attachment","inline"],"default":"attachment"},"content_id":{"type":"string","description":"For inline attachments"}}}}}},"EmailSendingHeaders":{"type":"object","properties":{"headers":{"type":"object","additionalProperties":{"type":"string"}}}},"EmailCustomVariables":{"type":"object","properties":{"custom_variables":{"type":"object","additionalProperties":{"type":"string"}}}},"EmailCategory":{"type":"object","properties":{"category":{"type":"string","maxLength":255}}},"EmailWithHtml":{"title":"HTML Only","allOf":[{"$ref":"#/components/schemas/EmailSenderRequired"},{"$ref":"#/components/schemas/EmailRecipients"},{"$ref":"#/components/schemas/EmailReplyTo"},{"$ref":"#/components/schemas/EmailSubjectRequired"},{"$ref":"#/components/schemas/EmailHtmlRequired"},{"$ref":"#/components/schemas/EmailAttachments"},{"$ref":"#/components/schemas/EmailSendingHeaders"},{"$ref":"#/components/schemas/EmailCustomVariables"},{"$ref":"#/components/schemas/EmailCategory"}]},"EmailHtmlRequired":{"type":"object","required":["html"],"properties":{"html":{"type":"string","minLength":1}}},"EmailWithTextAndHtml":{"title":"Text and HTML","allOf":[{"$ref":"#/components/schemas/EmailSenderRequired"},{"$ref":"#/components/schemas/EmailRecipients"},{"$ref":"#/components/schemas/EmailReplyTo"},{"$ref":"#/components/schemas/EmailSubjectRequired"},{"$ref":"#/components/schemas/EmailTextRequired"},{"$ref":"#/components/schemas/EmailHtmlRequired"},{"$ref":"#/components/schemas/EmailAttachments"},{"$ref":"#/components/schemas/EmailSendingHeaders"},{"$ref":"#/components/schemas/EmailCustomVariables"},{"$ref":"#/components/schemas/EmailCategory"}]},"EmailFromTemplate":{"title":"From Template","allOf":[{"$ref":"#/components/schemas/EmailSenderRequired"},{"$ref":"#/components/schemas/EmailRecipients"},{"$ref":"#/components/schemas/EmailReplyTo"},{"$ref":"#/components/schemas/TemplateUuidRequired"},{"$ref":"#/components/schemas/TemplateVariables"},{"$ref":"#/components/schemas/EmailAttachments"},{"$ref":"#/components/schemas/EmailSendingHeaders"},{"$ref":"#/components/schemas/EmailCustomVariables"}]},"TemplateUuidRequired":{"type":"object","required":["template_uuid"],"properties":{"template_uuid":{"type":"string","format":"uuid","description":"Email template UUID"}}},"TemplateVariables":{"type":"object","properties":{"template_variables":{"type":"object","description":"Template variable values"}}},"SentResponse":{"type":"object","properties":{"success":{"type":"boolean"},"message_ids":{"type":"array","description":"Message IDs (one per recipient)","items":{"type":"string"}}}},"SendEmailErrorResponse":{"type":"object","description":"Error responses from the sending API use `success: false` and an `errors` array of strings\n(unlike account APIs on `mailtrap.io`, which use `error` or a single `errors` string).\n","properties":{"success":{"type":"boolean"},"errors":{"type":"array","items":{"type":"string"}}}}},"responses":{"BadRequest":{"description":"Bad request. Fix errors listed in response before retrying.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/SendEmailErrorResponse"}}}},"Unauthorized":{"description":"Unauthorized. Check your API credentials.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/SendEmailErrorResponse"}}}},"Forbidden":{"description":"Forbidden. Verify domain or check permissions.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/SendEmailErrorResponse"}}}},"InternalError":{"description":"Internal server error. Retry later or contact support.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/SendEmailErrorResponse"}}}}}},"paths":{"/api/send":{"post":{"summary":"Send transactional email","description":"Send a single transactional email with text, HTML, or template content.\n\nUse this endpoint for:\n- Order confirmations\n- Password reset emails\n- Account notifications\n- Welcome emails\n- System alerts\n","operationId":"sendEmail","tags":["send-email"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"oneOf":[{"$ref":"#/components/schemas/EmailWithText"},{"$ref":"#/components/schemas/EmailWithHtml"},{"$ref":"#/components/schemas/EmailWithTextAndHtml"},{"$ref":"#/components/schemas/EmailFromTemplate"}]}}}},"responses":{"200":{"description":"Email successfully sent","content":{"application/json":{"schema":{"$ref":"#/components/schemas/SentResponse"}}}},"400":{"$ref":"#/components/responses/BadRequest"},"401":{"$ref":"#/components/responses/Unauthorized"},"403":{"$ref":"#/components/responses/Forbidden"},"500":{"$ref":"#/components/responses/InternalError"}}}}}}
```


---

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```
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