Self Assessment is a system HM Revenue and Customs (HMRC) uses to collect Income Tax.

Tax is usually deducted automatically from wages, pensions and savings. People and businesses with other income must report it in a tax return.

If you need to send one, you fill it in after the end of the tax year (5 April) it applies to.

Who must send a tax return

You must send a tax return if, in the last tax year (6 April to 5 April), you were:

• self-employed as a ‘sole trader’ and earned more than £1,000 (before taking off anything you can claim tax relief on)

• a partner in a business partnership

You will not usually need to send a return if your only income is from your wages or pension. But you may need to send one if you have any other untaxed income, such as:

• money from renting out a property

• tips and commission

• income from savings, investments and dividends

• foreign income

Check if you need to send a tax return if you’re not sure.

 

Other reasons for sending a return

You can choose to fill in a tax return to:

• claim some Income Tax reliefs

• prove you’re self-employed, for example to claim Tax-Free Childcare or Maternity Allowance

 

If you get Child Benefit

If your income (or your partner’s, if you have one) was over £50,000, you may need to send a return and pay the High Income Child Benefit Charge.

Deadlines

Send your tax return by the deadline.

If you did not send an online return last year, allow extra time (up to 20 working days) as you’ll need to register first. There are different ways to register if you’re:

• self-employed or a sole trader

• not self-employed

• registering a partner or partnership

Filling in your return

You need to keep records (for example bank statements or receipts) so you can fill in your tax return correctly.

You can get help filling in your return.

 

Paying your bill

HMRC will calculate what you owe based on what you report.

Pay your Self Assessment bill by 31 January.

How much tax you pay will depend on the Income Tax band you’re in. There’s a different rate for Capital Gains Tax if you need to pay it, for example you sell shares or a second home.

 

Penalties

You’ll get a penalty if you need to send a tax return and you miss the deadline for submitting it or paying your bill.

You’ll get a penalty of £100 if your tax return is up to 3 months late. You’ll have to pay more if it’s later, or if you pay your tax bill late. You’ll also be charged interest on late payments.

How to get help

If you need help with Self-Assessment, you can:

• appoint someone to fill in and send your tax return, for example an accountant, friend or relative - you can find an accountant accredited in the UK.

• watch videos and join webinars

• contact HM Revenue and Customs (HMRC) for general Self Assessment enquiries

• get help with your online account

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Help filling in your return

There’s introductory guidance on GOV.UK to:

• Capital Gains Tax if you’ve sold certain things like property or shares

• expenses if you’re an employee or self-employed

• Child Benefit if your income’s over £50,000

• tax on income from renting property

• tax on savings interest

• tax returns for business partnerships

• tax on income from abroad - or on your UK income if you live abroad

Guidance notes and help sheets

You can also read guidance in:

• the notes for each section of the tax return, for example ‘UK property notes’ if you’re completing that section

• HMRC’s Self Assessment helpsheets

 

Disclaimer: The information contained in this article is intended to be a guide and is not intended to be exhaustive. No action should be taken on the basis of information contained herein without obtaining the necessary advice. No responsibility can be accepted for loss or damages occasioned to any person acting or refraining from acting as a result of the material contained herein.

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