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Find out how well your organisation complies with the principles of the surveillance camera code of practice.
How to get online help with Self Assessment from HMRC by using our digital assistant, community forums, YouTube videos and online tools.
Cognitive testing of survey questions to measure economic impact of policy interventions: stage 3.
Research to track the 2022 to 2023 Self Assessment advertising campaign to understand and measure its effectiveness.
Taxpayers who are unsure if they need to submit a Self Assessment tax return can use HMRC's online tool to help them work out what they need to do.
Use supplementary pages SA904 to record foreign income and capital gains on the SA900 Trust and Estate Tax Return.
Find out how to appeal an individual or partnership Self Assessment penalty. For example, either online or by post using forms SA370 or SA371.
Use this technical documentation for individual returns if you're a software developer working with the Self Assessment online service.
Use supplementary pages SA104F to record full partnership income on your SA100 tax return.
If you’ve missed Self Assessment deadlines get an estimate of how much you’ll need to pay in penalties and interest
We welcome views on the case for reforming Income Tax Self Assessment registration for the self-employed and landlords.
Use supplementary pages SA906 to declare residence status on the SA900 Trust and Estate Tax Return.
Research report summarising the tracking of Self Assessment communications, measuring the effectiveness of the 2016 to 2017 Self Assessment campaign.
Find software suppliers for tax returns, supplementary pages and attachments.
Advice on what records you need to keep for tax purposes and how long you need to keep them.
Don’t include personal or financial information like your National Insurance number or credit card details.
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