HM Revenue & Customs (HMRC)
Collects taxes and National Insurance and pays Child Benefit. You deal with it for Income Tax, Self Assessment, PAYE and your tax code.
Home » Work and tax » Self Assessment tax return
Self Assessment tax return
Needed if you are self-employed or have income not taxed at source. Register by 5 October after the tax year; the online deadline is 31 January.
Official links
| Official source | Applies to |
|---|---|
| GOV.UK: Self Assessment tax returns www.gov.uk/self-assessment-tax-returns | Whole UK |
| GOV.UK: register for Self Assessment www.gov.uk/register-for-self-assessment | Whole UK |
Who handles it
Step by step
- Check if you need to send a return: for example self-employment, renting out property, foreign income or other untaxed income.
- Register by 5 October after the end of the tax year (which runs 6 April to 5 April). You will get a Unique Taxpayer Reference (UTR).
- Keep records of your income and expenses all year.
- Send your return online by 31 January (paper returns must arrive by 31 October).
- Pay what you owe by 31 January. If you make payments on account, there is a second payment by 31 July.
What you need
- Your National Insurance number (needed to register)
- Your Unique Taxpayer Reference (UTR)
- Records such as bank statements, invoices and receipts
Common mistakes
- Registering after 5 October or filing late: both can lead to penalties.
- Filing with an old account without reactivating it first, which delays your return.
- Not telling HMRC when you no longer need to send a return.
More in Work and tax
- Apply for a National Insurance number
- Prove your right to work
- HMRC personal tax account
- National Minimum Wage and Living Wage
- Find a job
- Workplace pensions
- Claim a tax refund
- Check or change your tax code
- Marriage Allowance
- Holiday entitlement and holiday pay
- Statutory Sick Pay (SSP)
- Maternity and paternity leave and pay