Who needs to file
You must file a self-assessment return if you: are self-employed with income over £1,000, have income over £100,000, have rental income over £2,500 per year, have untaxed income (interest, dividends), or HMRC tells you to. Register with HMRC by 5th October in the tax year after you first need to file.
What you need to gather
Our free self-assessment checklist covers everything: UTR number, National Insurance number, P60(s), P11D if applicable, self-employment income and expenses records, rental income details, savings interest statements, and any capital gains records. Gather these before sitting down to file.
The January problem
Most people file in January because the deadline is 31 January. But HMRC receives around half of all returns in January, making the service slow and support hard to reach. Filing before 31 October (the paper deadline) or in November/December produces the same result with less stress.
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