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Check the availability and any issues affecting the Self Assessment payment plan service.
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.
Get help if you’re a tax agent or adviser who has clients with Income Tax losses to declare on Self Assessment tax returns.
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 out how to report support payments relating to self-isolation due to coronavirus (COVID-19), on your Self Assessment tax return.
Reporting and paying tax on payments received for use of image rights, including payments made to an image rights company.
Details of record keeping, enquiries, completion of Self Assessment returns, and interpretation of 'merely incidental' duties.
Use this helpsheet to understand tax rules on non-resident entertainers and sportspersons.
Use this helpsheet to work out Foreign Tax Credit Relief for Capital Gains and how to complete the Trust and Estate tax return.
Get help if you’re a tax agent or adviser who has clients with capital allowances for plant and machinery to declare on Self Assessment and Company Tax returns.
Get help if you’re a tax agent or adviser who has clients with Capital Gains Tax for shares to declare on Self Assessment tax returns.
Get help if you’re a tax agent or adviser who has clients with Capital Gains Tax for trusts and estates income to declare on Self Assessment tax returns.
Find out how to work out Foreign Tax Credit Relief if you have overlap profits or you're claiming overlap relief.
Agent authorisation Self Assessment technical specifications for software developers.
If you received Horizon Shortfall Scheme (HSS) compensation between 6 April 2022 and 5 April 2023, you can get support about your Self Assessment tax return.
Find out how to complete a tax return for Lloyd's underwriters.
Use this technical documentation for partnership returns if you’re a software developer working with the Self Assessment Online service
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