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Find out the expectations for good use of generative artificial intelligence (AI) in commercial software products that help customers submit information to HMRC.
Check a list of software developers who can provide Customs Declaration Service software.
Find the schema and supporting documents for software developers who use Automatic Exchange of Information (AEOI).
Find HMRC payroll test data for software developers.
Find software developers that can help with entry summary declarations including safety and security declarations for imports.
Use this technical documentation for individual returns if you're a software developer working with the Self Assessment online service.
Use this guidance for support if you're a software developer working with the Self Assessment Online service.
Use this technical documentation for partnership returns if you’re a software developer working with the Self Assessment online service.
Use this technical documentation for trust and estate returns if you’re a software developer working with the Self Assessment online service.
Find software developers that can provide software to let you submit presentation of goods notifications for the safety and security process when goods arrive in Northern Ireland.
Find out how to create a CSV file to submit your declaration, what file layout to use and how to resolve problems with file upload failures.
Find the schema and supporting documents for software developers, or agents, acting on behalf of merchant acquirers who send returns to HMRC.
Find out about the Real Time Information (RTI) Rules and Interface Management (RIM) artefacts and supporting technical specifications for software developers.
Use this technical documentation for individual returns if you're a software developer working with the Self Assessment Online service.
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