Verify individual From addresses
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openapi: 3.2.0
info:
title: SMTP2GO SINGLE SENDER EMAILS API
version: 3.0.4
description: The SMTP2GO v3 REST API for sending transactional email and SMS, managing sender domains and single sender emails, SMTP users, API keys, IP allow lists and IP auth, templates, webhooks, suppressions, subaccounts, dedicated IPs, email archive, activity search and delivery statistics. Every operation is a POST (with a PATCH variant on two paths) carrying a JSON body; authentication is an API key supplied in the X-Smtp2go-Api-Key header or as an api_key field in the request body.
contact:
name: SMTP2GO Support
url: https://support.smtp2go.com/
termsOfService: https://www.smtp2go.com/terms/
x-harvest:
source: https://developers.smtp2go.com/mcp
method: MCP tools/call get-endpoint, one call per path+method, assembled verbatim
harvested: '2026-08-13'
server_info:
name: SMTP2GO-API-Docs
version: 3.0.4
note: SMTP2GO does not publish a single fetchable OpenAPI URL; the ReadMe registry path answers 429 to non-browser clients. The provider's own remote MCP server returns the authoritative OpenAPI 3.1.0 fragment for each endpoint anonymously, and those 73 fragments are merged here without modification.
servers:
- url: https://api.smtp2go.com/v3
description: Regionless
- url: https://us-api.smtp2go.com/v3
description: US Region
- url: https://eu-api.smtp2go.com/v3
description: EU Region
- url: https://au-api.smtp2go.com/v3
description: AU Region
security:
- sec0: []
tags:
- name: SINGLE SENDER EMAILS
description: Verify individual From addresses
paths:
/single_sender_emails/add:
post:
tags:
- SINGLE SENDER EMAILS
summary: Add a single sender email
description: Use the API to add a single sender email address to your account, to use from which to send mail. If the email address has previously been added and not yet verified, this action will simply resend the verification email.
operationId: add-a-single-sender-email
requestBody:
content:
application/json:
schema:
type: object
required:
- email_address
properties:
email_address:
type: string
description: The email address that you wish to send emails from
default: send@example.com
message:
type: string
description: (Optional) If provided, will add a text only message to the email.
subaccount_id:
type: string
description: If you wish to make this API call on behalf of a subaccount then include its unique ID here
responses:
'200':
description: Single sender email added
content:
application/json:
examples:
Result:
value:
just_returns_this: ok
schema:
type: object
required:
- request_id
properties:
request_id:
type: string
example: e023461c-8c86-11e9-b984-408d5cce2644
'400':
description: '400'
content:
application/json:
examples:
Result:
value:
request_id: 22e5acba-43bf-11e6-ae42-408d5cce2644
data:
error: You do not have permission to access this API endpoint
error_code: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED
schema:
type: object
properties:
request_id:
type: string
example: 22e5acba-43bf-11e6-ae42-408d5cce2644
data:
type: object
properties:
error:
type: string
example: You do not have permission to access this API endpoint
error_code:
type: string
example: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED
deprecated: false
/single_sender_emails/remove:
post:
tags:
- SINGLE SENDER EMAILS
summary: Remove a single sender email
description: Remove a single sender email address from your account. Include the address to remove as the email_address parameter.
operationId: remove-a-single-sender-email
requestBody:
content:
application/json:
schema:
type: object
required:
- email_address
properties:
email_address:
type: string
description: The email address to remove from your Single Sender Emails
default: send@example.com
subaccount_id:
type: string
description: If you wish to make this API call on behalf of a subaccount then include its unique ID here
responses:
'200':
description: Single sender email removed
content:
application/json:
examples:
Result:
value:
just_returns_this: OK
schema:
type: object
required:
- request_id
properties:
request_id:
type: string
example: 22e5acba-43bf-11e6-ae42-408d5cce2644
data:
type: string
'400':
description: '400'
content:
application/json:
examples:
Result:
value:
request_id: 22e5acba-43bf-11e6-ae42-408d5cce2644
data:
error: You do not have permission to access this API endpoint
error_code: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED
schema:
type: object
properties:
request_id:
type: string
example: 22e5acba-43bf-11e6-ae42-408d5cce2644
data:
type: object
properties:
error:
type: string
example: You do not have permission to access this API endpoint
error_code:
type: string
example: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED
deprecated: false
/single_sender_emails/view:
post:
tags:
- SINGLE SENDER EMAILS
summary: View single sender emails
description: Returns a list of single sender email addresses on your account, along with their verification status. If you include a email_address, the response will only include items matching this search.
operationId: view-all-single-sender-emails
requestBody:
content:
application/json:
schema:
type: object
properties:
email_address:
type: string
description: (Optional) If provided, only return email addresses that match value
subaccount_id:
type: string
description: If you wish to make this API call on behalf of a subaccount then include its unique ID here
responses:
'200':
description: List of single sender emails
content:
application/json:
examples:
Result:
value:
data:
request_id: e023461c-8c86-11e9-b984-408d5cce2644
senders:
- email_address: test@test.com
verified: true
schema:
type: object
properties:
data:
type: object
required:
- request_id
- senders
properties:
request_id:
type: string
example: e023461c-8c86-11e9-b984-408d5cce2644
senders:
type: array
items:
type: object
required:
- email_address
- verified
properties:
email_address:
type: string
example: test@test.com
verified:
type: boolean
example: true
default: true
'400':
description: '400'
content:
application/json:
examples:
Result:
value:
request_id: 22e5acba-43bf-11e6-ae42-408d5cce2644
data:
error: You do not have permission to access this API endpoint
error_code: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED
schema:
type: object
properties:
request_id:
type: string
example: 22e5acba-43bf-11e6-ae42-408d5cce2644
data:
type: object
properties:
error:
type: string
example: You do not have permission to access this API endpoint
error_code:
type: string
example: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED
deprecated: false
components:
securitySchemes:
sec0:
type: apiKey
in: header
name: X-Smtp2go-Api-Key
x-default: ${SMTP2GO_API_KEY}