Self-Assessment Tax Return

The annual tax filing process for UK self-employed individuals and business owners, declaring income, allowable expenses, and calculating tax owed to HMRC.

Every UK founder with self-employment income must file a self-assessment return. Missing the January 31st deadline triggers automatic fines starting at £100. Keeping records year-round makes this straightforward.

A founder registered self-employed from April. She tracks all business income and expenses in a spreadsheet throughout the year. In January, her accountant files her return in an afternoon, tax bill: expected and already saved.