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Use this guidance for support if you're a software developer working with the Self Assessment Online service.
Data submission specifications for the children looked after (CLA) return for 2021 to 2022.
Use this technical documentation for individual returns if you're a software developer working with the Self Assessment Online service.
Internet submissions technical specifications for Real Time Information online software developers.
Minimum technical specification for manufacturers of chargepoint units for residential properties covered by OZEV chargepoint grant schemes.
Use this technical documentation for individual returns if you're a software developer working with the Self Assessment online service.
Charities repayments claims technical specifications for software developers.
Find guidance for software developers working with the Corporation Tax online service.
Data submission specifications for the children looked after (CLA) return for 2024 to 2025.
Use this technical documentation for partnership returns if you’re a software developer working with the Self Assessment online service.
Guidance for EC Sales List online developers on Government Gateway.
Individual returns technical specifications for Self Assessment Online software developers.
Find schema and technical specifications for Construction Industry Scheme Online software developers.
Agent authorisation PAYE technical specifications for software developers.
Real Time Information (RTI) Rules and Interface Management (RIM) artefacts and supporting technical specifications for software developers.
Returns technical specifications for Self Assessment Online software developers.
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