Connection and callback requirements
Endpoints must be called through a server-to-server connection supporting HTTP/2, TLS 1.2 or 1.3, and GET and POST requests. The callback must use a fully qualified domain name, accept parameters, and contain no IP address, port number, hash or wildcard. Sandbox and production require different callback URLs.
Onboarding and annual changes
Assess the service specifications, authentication guidance and recommended controls before registering interest by 30 September. IRAS publishes changes arising from tax rules or government initiatives by September each year. If software provides an employee copy, align its fields with official forms and include the required AIS retention statement rather than prompting duplicate declaration.
Official source
A concise, independent Apex Gateway guide based on the official English source, not a reproduction of the complete document. Consult the original for full conditions, exceptions and subsequent updates.
Read the official source ↗