In the UK the majority of people do absolutely nothing. Your wage slip says how much tax you've paid each month (through the PAYE system) and then at the end of

In the UK the majority of people do absolutely nothing. Your wage slip says how much tax you've paid each month (through the PAYE system) and then at the end of the tax year your company sends you a P60 form (https://www.gov.uk/paye-forms-p45-p60-p11d/p60 https://www.gov.uk/paye-forms-p45-p60-p11d/p60) which is simply a pre-filled summary of all the tax you paid that year. That's the case for anyone with the most common case of a single salaried job. If you have a more complex situation (dividends from company share, taxable investments, multiple jobs) then you need to fill in a self-assessment form. I did one last year and it was all done online and took about an hour in total.