I earn money from a side hustle. Do I need to declare it?

If your side hustle income is over £1,000 in a tax year, yes — you'll need to declare it on a Self Assessment return. The £1,000 Trading Allowance means you don't pay tax on the first £1,000 of self-employment or casual income, but once you exceed that you need to register and file. It doesn't matter whether you're being paid in cash, through PayPal, via platforms like Etsy, Vinted, or Deliveroo, or in any other way — if it's income for a service or goods you're selling, it counts. HMRC has been increasingly active in tracking income through digital platforms, so it's worth getting it right.