openapi: 3.2.0 info: title: SMTP2GO ALLOWED SENDERS 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: ALLOWED SENDERS description: Manage the allowed/restricted senders list paths: /allowed_senders/add: post: tags: - ALLOWED SENDERS summary: Add allowed senders description: Add one or more email addresses and domain names to your Allowed or Restricted Senders List. How this list of email addresses and domain names are used is shown by the current 'mode' value; if the Restrict Senders setting is on, they will form either a whitelist or blacklist. If the setting is off, the list will be disabled. Further details of the associated setting are found in the SMTP2GO Guides. Details of how this mode can be set via the update end-point, are given further in the documentation. A post to this endpoint will return a success, even if the Restrict Senders setting is not in use. operationId: add-allowed-senders requestBody: content: application/json: schema: type: object required: - allowed_senders properties: allowed_senders: type: array description: Array of email addresses and domain names. default: - test-person@example.com - other@example.com items: type: string 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: Allowed Senders list updated content: application/json: examples: Example: value: request_id: b8f3c2b4-63ca-11ed-b66a-f23c9216ce11 data: allowed_senders: - test@test.com mode: disabled schema: type: object required: - request_id - data properties: request_id: type: string example: 40cbb6f2-935f-11e7-b5be-480fcf01a6f2 data: type: object required: - allowed_senders - mode properties: allowed_senders: type: array description: A list of email addresses and domain names items: type: string example: test-person@example.com mode: type: string description: A string indicating how the list of email address and domain names is interpreted. example: whitelist enum: - whitelist - blacklist - disabled '400': description: '400' content: application/json: examples: Example: value: request_id: 22e5acba-43bf-11e6-ae42-408d5cce2644 data: error_code: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED error: You do not have permission to access this API endpoint schema: type: object properties: request_id: type: string example: 22e5acba-43bf-11e6-ae42-408d5cce2644 data: type: object properties: error_code: type: string example: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED error: type: string example: You do not have permission to access this API endpoint deprecated: false /allowed_senders/remove: post: tags: - ALLOWED SENDERS summary: Remove allowed senders description: 'Remove one or more emails addresses or domain names stored in your Allowed or Restricted Senders List. Note: In the event that any of the email addresses or domains do not feature in the list, no error will be raised.' operationId: remove-allowed-senders requestBody: content: application/json: schema: type: object required: - allowed_senders properties: allowed_senders: type: array description: Array of email addresses and domain names to remove. default: - test-person@example.com items: type: string 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: Allowed Sender Removed content: application/json: examples: Example: value: request_id: 40cbb6f2-935f-11e7-b5be-480fcf01a6f2 data: allowed_senders: - test-person@example.com mode: disabled schema: type: object required: - request_id - data properties: request_id: type: string example: 40cbb6f2-935f-11e7-b5be-480fcf01a6f2 data: type: object required: - allowed_senders - mode properties: allowed_senders: type: array description: A list of email addresses and domain names items: type: string example: test-person@example.com mode: type: string description: A string indicating how the list of email address and domain names is interpreted. example: whitelist enum: - whitelist - blacklist - disabled '400': description: '400' content: application/json: examples: Example: value: request_id: 22e5acba-43bf-11e6-ae42-408d5cce2644 data: error_code: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED error: You do not have permission to access this API endpoint schema: type: object properties: request_id: type: string example: 22e5acba-43bf-11e6-ae42-408d5cce2644 data: type: object properties: error_code: type: string example: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED error: type: string example: You do not have permission to access this API endpoint deprecated: false /allowed_senders/update: post: tags: - ALLOWED SENDERS summary: Update allowed senders description: Replace the email addresses and domain names on your Allowed or Restricted Senders List using this endpoint. How the email addresses and domain names are used is defined in the current 'mode' value - further details of these modes are found in the SMPT2GO Guides. Note that a post to this endpoint will return a success, even if the setting is not in use. operationId: update-allowed-senders requestBody: content: application/json: schema: type: object required: - allowed_senders - mode properties: allowed_senders: type: array description: Array of email addresses and domain names. default: - test-person@example.com - other@example.com items: type: string mode: type: string description: A string indicating how the list of email address and domain names is interpreted. and should be one of 'whitelist', 'blacklist' or 'disabled'.
Warning: Changing the mode to 'whitelist' or 'blacklist' disables the 'Sender Domains' and 'Single Sender Emails' features.
default: whitelist enum: - whitelist - blacklist - disabled 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: Allowed Senders list updated content: application/json: examples: Example: value: request_id: 40cbb6f2-935f-11e7-b5be-480fcf01a6f2 data: allowed_senders: - test-person@example.com - otherexample.com mode: whitelist schema: type: object required: - request_id - data properties: request_id: type: string example: 40cbb6f2-935f-11e7-b5be-480fcf01a6f2 data: type: object required: - allowed_senders - mode properties: allowed_senders: type: array description: A list of email addresses and domain names items: type: string example: test-person@example.com mode: type: string description: A string indicating how the list of email address and domain names is interpreted. example: whitelist enum: - whitelist - blacklist - disabled '400': description: '400' content: application/json: examples: Example: value: request_id: 22e5acba-43bf-11e6-ae42-408d5cce2644 data: error_code: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED error: You do not have permission to access this API endpoint schema: type: object properties: request_id: type: string example: 22e5acba-43bf-11e6-ae42-408d5cce2644 data: type: object properties: error_code: type: string example: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED error: type: string example: You do not have permission to access this API endpoint deprecated: false /allowed_senders/view: post: tags: - ALLOWED SENDERS summary: View allowed senders description: Returns the email addresses and domain names on your Allowed or Restricted Senders list, as well as the Restrict Senders setting, which dictates how they are interpreted. operationId: view-allowed-senders requestBody: content: application/json: schema: type: object required: [] properties: 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 Allowed Senders content: application/json: examples: Example: value: request_id: 40cbb6f2-935f-11e7-b5be-480fcf01a6f2 data: allowed_senders: - test@test.com mode: disabled schema: type: object required: - request_id - data properties: request_id: type: string example: 40cbb6f2-935f-11e7-b5be-480fcf01a6f2 data: type: object required: - allowed_senders - mode properties: allowed_senders: type: array description: A list of email addresses and domain names items: type: string example: test-person@example.com mode: type: string description: A string indicating how the list of email address and domain names is interpreted. example: whitelist enum: - whitelist - blacklist - disabled '400': description: '400' content: application/json: examples: Example: value: request_id: 22e5acba-43bf-11e6-ae42-408d5cce2644 data: error_code: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED error: You do not have permission to access this API endpoint schema: type: object properties: request_id: type: string example: 22e5acba-43bf-11e6-ae42-408d5cce2644 data: type: object properties: error_code: type: string example: E_ApiResponseCodes.ENDPOINT_PERMISSION_DENIED error: type: string example: You do not have permission to access this API endpoint deprecated: false components: securitySchemes: sec0: type: apiKey in: header name: X-Smtp2go-Api-Key x-default: ${SMTP2GO_API_KEY}