Filing a tax return can feel daunting but don’t panic. There’s plenty of support and advice to help complete your tax return and pay the right amount of tax.
Here is some information to help you work out how to complete your tax return. It’s not a comprehensive guide, so make sure you get help or professional advice if you feel you need it (there are ways to find this below).
Fill out the form
The basic return form SA100 has eight pages and collects information about:
- your income
- whether you want to claim one of the main tax reliefs
- how you would like to deal with any tax payment or refunds
You only need to complete the sections of the tax return that are relevant to your income. They should be for the tax year covered by the return. For example, the tax year 2025/26 covers the time from 6 April 2025 to 5 April 2026.
Fill out the sections that are relevant to you and leave the rest blank.
HMRC provide a guide each year to help fill out the form: How to fill in your tax return.
Short tax returns
There is a short, four-page, tax return that HMRC issue for some taxpayers with very straightforward tax affairs who must still file a tax return. This form (SA200) is not available from the HMRC website, and you cannot ask for a short return.
Get help if you need it
If your tax situation is complicated or you’re struggling with the form, try and find someone to help you. Here are some ways to find help:
- Contact HMRC by phone or online. Here are different ways to contact HMRC. They also have videos and articles with information and online tools to help you complete your Self Assessment.
- Call us. Our helpline offers free, expert tax advice to people who meet certain criteria. Find out more about our helpline.
- Speak to a tax advisor. Find out more about choosing an advisor.
Be accurate and honest
Double check all the information you put on your return. It’s best to make sure it’s as accurate as possible.
However, mistakes can happen. There are ways to change your return if you realise you’ve made a mistake after you’ve filed it in.
It is best to be honest about your income and expenses to avoid any issues.
Keep proof that you’ve submitted your tax return
If you file your return online, make sure you generate a submission receipt and print it out or save a copy.
If you complete a paper tax return, make sure you get proof of postage from the Post Office.