What do I declare for income from self-employment if I made a loss in the relevant financial year?

You must declare £0 if you've made a loss.

You must make a note of your loss in the free text box at the end on the income assessment and provide evidence such as:

• personal tax calculation or computation statement from HM Revenue and Customs (HMRC)
• self assessment tax return
• statement of accounts
• accountant's letter

The loss from self-employment cannot be used to offset other types of income.