SMTP2GO

SMTP2GO SENDER DOMAINS API

Add, verify and manage sender domains, tracking and return-path subdomains

GitHub OpenAPI

Operations 7

Each operation below carries the questions people ask an LLM about it and the instructions they give an agent to run it. Generated by API Evangelist overlay

POST /domain/add Add a sender domain · Add a sender domain #
Ask an LLM
“How do I add my domain so I can send email from it?”
“Can I set a custom tracking and return-path subdomain when adding a domain?”
Tell an agent
Add sender domain {domain}.
Add {domain} with tracking subdomain {tracking_subdomain} and return-path {returnpath_subdomain}.
POST /domain/remove Remove a sender domain · Remove a sender domain #
Ask an LLM
“How do I delete a sender domain I no longer use?”
“Can I remove a sender domain from a subaccount?”
Tell an agent destructive · confirm first
Remove sender domain {domain}.
Delete {domain} from subaccount {subaccount_id}.
POST /domain/returnpath Change a domain's return-path subdomain · Edit the return-path subdomain #
Ask an LLM
“How do I change where bounces are returned for my sender domain?”
“Can I rename the return-path subdomain on a verified domain?”
Tell an agent
Change the return-path subdomain of {domain} from {old_subdomain} to {new_subdomain}.
Set the bounce return-path for {domain} to {new_subdomain}, replacing {old_subdomain}.
POST /domain/subaccount_access Share a sender domain with subaccounts · Edit subaccount access #
Ask an LLM
“Can my subaccounts send from a domain verified on the master account?”
“How do I give future subaccounts access to a sender domain automatically?”
Tell an agent
Let subaccounts {subaccounts} send from {domain}.
Grant {subaccounts} access to {domain} and set future subaccount access to {future_subaccounts}.
POST /domain/tracking Change a domain's tracking subdomain · Edit the tracking subdomain #
Ask an LLM
“How do I change the subdomain used to track opens and clicks?”
“Can I rename the tracking subdomain for one sender domain?”
Tell an agent
Change the tracking subdomain of {domain} from {old_subdomain} to {new_subdomain}.
Use {new_subdomain} instead of {old_subdomain} for open and click tracking on {domain}.
POST /domain/verify Verify a sender domain now · Verify a sender domain #
Ask an LLM
“How do I verify my sender domain without waiting for the periodic check?”
“Why isn't my domain verified yet, and can I trigger a check right away?”
Tell an agent
Verify sender domain {domain} now.
Run verification on {domain} for subaccount {subaccount_id}.
POST /domain/view List sender domains · View sender domains #
Ask an LLM
“Which sender domains are on my account and are they verified?”
“Can I see the DNS status of one sender domain?”
Tell an agent
List my sender domains.
Show the details of sender domain {domain}.

Documentation

📖
Documentation
https://developers.smtp2go.com/docs/introduction-guide
📖
GettingStarted
https://developers.smtp2go.com/docs/getting-started
📖
RateLimits
https://developers.smtp2go.com/docs/rate-limiting
📖
APIReference
https://developers.smtp2go.com/reference/general-api-resources

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/smtp2go/refs/heads/main/openapi/smtp2go-sender-domains-api-openapi.yml

Other Resources

🔗
Endpoints
https://developers.smtp2go.com/docs/endpoints

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OpenAPI Specification

smtp2go-sender-domains-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: SMTP2GO SENDER DOMAINS 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:


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# Full source: https://raw.githubusercontent.com/api-evangelist/smtp2go/refs/heads/main/openapi/smtp2go-sender-domains-api-openapi.yml