Setting up as self-employed and tax

Budget for your Self Assessment tax bill if you're self-employed(link is external)
A tool to help you budget for your first Self Assessment tax bill if you're self-employed

Set up as a sole trader(link is external)
Sole traders must register with HM Revenue and Customs (HMRC) and follow certain rules on running and naming their business

HMRC calculators and tools(link is external)
HM Revenue and Customs calculators and tools to help you work out your tax