Answers · UK 2025/26
Do I need to file a UK Self Assessment tax return?
You must file Self Assessment if self-employed earning over £1,000, partner in business, landlord with rental income, made CGT gains over £3,000, earned over £150,000, or got dividends/interest above allowances. Deadline: 31 January after tax year end (online).
Full answer
You must register for and file Self Assessment if any of these apply: self-employed earning over £1,000 (trading allowance threshold); company director; landlord with rental income over £1,000 (property allowance); partner in a business partnership; sold assets generating Capital Gains Tax (gains above £3,000 in 2025/26); earning total income over £150,000; received dividends above £500 (allowance reducing further) or savings interest above Personal Savings Allowance; child benefit clawback (HICBC) where one parent earns £60k-£80k; received tips, commission or untaxed income; foreign income. Register by 5 October following tax year end. Filing deadlines: paper 31 October, online 31 January following tax year end. Late filing penalty £100 immediately, then accruing daily. Make payments by 31 January (balancing payment + first payment on account) and 31 July.
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This answer is informational only and does not constitute financial, tax or legal advice. Figures are for the 2025/26 UK tax year. See our methodology and sources.