Every individual who has sources of income that have not been taxed under PAYE (Pay As You Earn) must declare their income to HM Revenue & Customs (HMRC) annually by completing a self-assessment tax return. This applies to individuals including the self-employed, partners in a business partnership, individuals with investment or rental income and company directors.

This factsheet explains the business records that must be kept by self-employed people in order to complete a tax return and covers how to complete and submit the return. The deadlines for submitting returns and paying tax, the penalties for missing deadlines, and how to correct a tax return and appeal against a tax decision are also explained.