188体育

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

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

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

You must send a return if HMRC asks you to.

Sending your return

You can file your Self Assessment tax return online.

If you need a paper form you can:

• download the SA100 tax return form
• call HMRC and ask for the SA100 tax return form

Deadlines

Send your tax return by the deadline.

You must tell HMRC by 5 October if you need to complete a tax return and you have not sent one before. You could be fined if you do not.

You can tell HMRC by registering for Self Assessment. Check how to register for Self Assessment.

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.

You must send a tax return if, in the last tax year (6 April to 5 April), any of the following applied:

• you were self-employed as a 鈥榮ole trader鈥� and earned more than 拢1,000 (before taking off anything you can claim tax relief on)
• you were a partner in a business partnership
• you had to pay Capital Gains Tax when you sold or 鈥榙isposed of鈥� something that increased in value
• you had to pay the High Income Child Benefit Charge

You may also need to send a tax return if you have any 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

You can check if you need to send a tax return if you鈥檙e 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鈥檙e self-employed, for example to claim Tax-Free Childcare or Maternity Allowance
• pay voluntary National Insurance contributions

You must register for Self Assessment by 5 October if you need to complete a tax return and you have not sent one before.听

Check how to register for Self Assessment.听

If you鈥檙e new to Self Assessment, you鈥檒l need to keep records (for example bank statements or receipts) so you can fill in your tax return correctly.听

Preparing for your tax bill听

You鈥檒l need to pay your tax bill by 31 January.听

To prepare, once you鈥檝e registered you can:听

• estimate how much tax you might need to pay听
• set up monthly or weekly payments to help you budget for your bill听
• send your tax return any time after 5 April - doing it earlier means you鈥檒l know what you owe

You can send a tax return by either:听

• submitting an online return听听
• sending a paper return听

You can get help filling in your return.听

When to send your tax return听

Check the filing deadlines. The deadline for sending a paper return is before the deadline for an online return.听

You can send your return any time after 5 April. Sending it earlier means you:听

• find out what you owe听
• can budget - if you want to make weekly or monthly payments听
• have time to pay your bill by 31 January听
• can set up a payment plan, if you do not think you can pay on time

Submit an online return听听

You can file your Self Assessment tax return online.

Send a paper return听

If you need a paper copy of the main Self Assessment tax return you can:听

• download the SA100 tax return form听
• call HMRC and ask for the SA100 tax return form听

If you need to send a tax return for trustees of a registered pension, you must download form SA970.听

You can download all other forms and supplementary pages.听

After sending your paper return, you can check when to expect a reply from HMRC.听

Use commercial software to send a return听

You can use commercial software:听

• for a partnership听
• for a trust and estate听
• if you get income from a trust听
• if you lived abroad as a non-resident听
• if you鈥檙e a Lloyd鈥檚 underwriter听
• if you鈥檙e a religious minister听
• to report profits made on selling or disposing of more than one asset (鈥榗hargeable gains鈥�)听

Find a commercial software supplier.

You must tell HMRC as soon as possible if you believe you no longer need to send a tax return.

HMRC needs time to review your request before the Self Assessment deadline of 31 January.

When you no longer need to send a tax return

You might no longer need to send a return because, for example:

• you鈥檝e stopped being self-employed
• you no longer rent out property
• you no longer pay the High Income Child Benefit Charge

How to tell HMRC

Sign in to your account and to:

• close your Self Assessment account
• ask to be removed from Self Assessment for a specific tax year

You鈥檒l need to provide your National Insurance number and your UTR number.

If you cannot fill in the online form you can also contact HMRC by phone or post.

If you鈥檙e no longer self-employed

You also need to tell HMRC that you鈥檝e stopped being self-employed.

If you鈥檝e already told HMRC that your self-employment has ended, HMRC may still ask you to send tax returns for future years.

If you鈥檝e checked and you do not need to send a tax return, you鈥檒l need tell HMRC.

What happens next

You can track the progress of your form in your .

HMRC听will write to you and confirm if you need to send a return.

HM Revenue and Customs (HMRC) must receive your tax return and any money you owe by the deadline.

Deadline for telling HMRC you need to complete a return

You must tell HMRC by 5 October if you need to complete a tax return and have not sent one before.

You can tell HMRC by registering for Self Assessment.

Deadline for submitting a paper return

If you鈥檙e sending a paper tax return, you must submit it by midnight 31 October 2025.

Deadline for submitting an online return

If you鈥檙e sending an online tax return, you must submit it by midnight 31 January 2026.

If you want HMRC to automatically collect tax you owe from your wages and pension, submit your online return by 30 December. Find out if you are eligible to pay this way.

Deadlines for paying tax you owe

You need to pay the tax you owe by midnight 31 January 2026.

There鈥檚 usually a second payment deadline of 31 July if you make advance payments towards your bill (known as 鈥�payments on account鈥�).

You鈥檒l usually pay a penalty if you鈥檙e late. You can appeal against a penalty if you have a reasonable excuse.

To avoid a payment penalty, you can 鈥榚stimate your Self Assessment tax bill鈥� before sending your tax return to:听

• give you an idea of what your bill is likely to be听

• allow you to budget and pay on time

If you do not know your profit for the whole tax year

You might not know what your profit will be for the whole tax year if, for example:

• your 鈥榓ccounting period鈥� ends at a different time to the end of the tax year
• your 鈥榓ccounting period鈥� is different to your 鈥榖asis period鈥�
• you鈥檙e waiting for a valuation

If you do not know what your profit will be for the whole tax year before the reporting deadline, you should work out what it鈥檚 likely to be (known as 鈥榩rovisional figures鈥�) and include those.

You should tell HMRC that you鈥檝e used provisional figures when you submit your return.

When you find out what your profit was for the whole tax year, you鈥檒l need to 鈥�change your return. You have 12 months from the Self Assessment deadline to make these changes.

If more tax is due, you鈥檒l need to pay interest on the difference between your estimates and the final figures. The interest will be worked out from the original due date for payment. If you have overpaid tax then you鈥檒l get interest paid to you.

When the deadline is different

HMRC must receive a paper tax return by 31 January if you鈥檙e a trustee of a registered pension scheme or a non-resident company. You cannot send a return online.

Partnership returns if you have a company as a partner

If your partnership鈥檚 accounting date is between 1 February and 5 April and one of your partners is a limited company, the deadline for:

• online returns is 12 months from the accounting date
• paper returns is 9 months from the accounting date

2023 to 2024 tax year and earlier

The Self Assessment deadline for these tax years has passed. Send your tax return or payment as soon as possible - you鈥檒l have to pay a penalty.

You鈥檒l get a penalty if you need to complete a tax return and you:听

• send your return late听
• pay your tax bill late听

You can estimate your penalty听for late Self Assessment tax returns and payments.听

If you register for Self Assessment late听

If you register after 5 October and do not pay all of your tax bill by 31 January, you鈥檒l get a 鈥榝ailure to notify鈥� penalty.听听

This penalty is based on the amount still left to pay and you鈥檒l receive it within 12 months after HMRC receive your Self Assessment tax return.听

You can find more information on 鈥榝ailure to notify鈥� penalties.

If you send your tax return late听

You鈥檒l get the following late filing penalties:听

• an initial 拢100 penalty听
• after 3 months, additional daily penalties of 拢10 per day, up to a maximum of 拢900听
• after 6 months, a further penalty of 5% of the tax due or 拢300, whichever is greater听
• after 12 months, another 5% or 拢300 charge, whichever is greater听

To avoid this, send your Self Assessment tax return as soon as possible.听

If you pay your tax late听

You鈥檒l get penalties of 5% of the tax unpaid at:听

• 30 days听
• 6 months听
• 12 months听

You鈥檒l also be charged interest on the amount owed. To avoid this, pay your Self Assessment tax bill听as soon as possible.听

Paying a penalty听

You must pay within 30 days of the date on the penalty notice. Find out how to pay a penalty.

If you disagree with a penalty听

If you have a reasonable excuse, you can appeal against a penalty.

You can make a change to a tax return after you filed it, for example because you made a mistake.

Your bill will be updated based on what you report. You may have to pay more tax or be able to claim a refund.

Updating your tax return

You can correct a tax return within 12 months of the Self Assessment deadline, online or by sending another paper return.

Example

If you miss the deadline or if you need to make a change to a return from an earlier tax year you鈥檒l need to write to HMRC.

Online tax returns

You must wait 3 days (72 hours) after filing before updating your return.

1. .

2. From 鈥榊our tax account鈥�, choose 鈥橲elf Assessment account鈥�.

3. Choose 鈥楳ore Self Assessment details鈥�.

4. Choose 鈥楢t a glance鈥� from the left-hand menu.

5. Choose 鈥楾ax return options鈥�.

6. Choose the tax year for the return you want to amend.

7. Go into the tax return, make the corrections and file it again.

Paper tax returns

For the main Self Assessment tax return you can:

• download the SA100 tax return form
• call HMRC and ask for the SA100 tax return form

You can download all other forms and supplementary pages.

You then need to send the corrected pages to the address on your Self Assessment paperwork.

Write 鈥榓mendment鈥� on each page and include your name and Unique Taxpayer Reference (UTR) - this is on previous tax returns or letters from HMRC.

If you cannot find the address, you can send your corrections to:

If you used commercial software

Contact the software provider for help correcting your tax return. Contact HMRC if your software is not able to make corrections.

Changes to your bill

You鈥檒l see your amended bill straight away if you updated your tax return online. Within 3 days, your statement will also show:

• the difference from the old one, so you can see whether you owe more or less tax
• any interest

To view this, and choose 鈥榁iew statements鈥� from the left-hand menu.

If you鈥檙e owed tax

You may be able to claim a tax refund.

If you need to pay more tax

Your updated bill will also show:

• the deadline for paying
• the effect on any payments on account you need to make

If you sent an updated paper return

HMRC will send you an updated bill. You can check when you can expect a reply from HMRC.

They鈥檒l pay any refund directly into your bank account, as long as you include your bank details on your tax return.

If you鈥檝e missed the deadline to change your return

You must contact HMRC in writing if you need to make changes to your tax return more than 12 months after the Self Assessment deadline. This includes making a change to an earlier tax year.

You鈥檒l also need to write HMRC a letter to:

• report income you did not include in your tax return
• claim overpayment relief (if you think you鈥檝e overpaid tax)

You can claim overpayment relief up to 4 years after the end of the tax year it relates to.

What to include

You must include:

• the tax year you鈥檙e correcting
• why you think you鈥檝e paid too much or little tax
• how much you think you鈥檝e over or underpaid
• your signature (no one else can sign on your behalf)

If you鈥檙e making an overpayment relief claim, you must also include in your letter:

• that you鈥檙e making a claim for overpayment relief
• if you鈥檝e previously made an appeal for the same payment
• a signed declaration saying that the details you鈥檝e given are 鈥榗orrect and complete to the best of your information and belief鈥�

You also need to keep evidence that you鈥檝e paid tax through Self Assessment for the relevant period as HMRC may ask for this at a later date.

You can also tell HMRC how you want to be repaid in your letter.

You may be able to get a tax refund (also known as a 鈥榬epayment鈥� or 鈥榬ebate鈥�) if you鈥檝e paid too much tax. You can check how to claim a tax refund.

If you鈥檝e already claimed a tax refund

You can听check when you can expect a reply from HMRC about your claim.

The status of your refund may show as 鈥榩ending鈥� in your online tax account. This means that the refund has been created but still needs to be approved and paid.

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
• watch videos and join webinars
• contact HM Revenue and Customs (HMRC) for general Self Assessment enquiries
• get technical help with your online account

Help filling in your return

There鈥檚 introductory guidance on 188体育 to:

• Capital Gains Tax if you鈥檝e sold certain things like property or shares
• expenses if you鈥檙e an employee or self-employed
• High Income Child Benefit Charge听if your income is over the threshold
• tax on income from renting property
• tax on savings interest
• tax on income from abroad - or on your UK income if you live abroad

Guidance notes and helpsheets

You can also read guidance in:

• the notes for each section of the tax return, for example 鈥�UK property notes鈥� if you鈥檙e completing that section
• HMRC鈥檚 Self Assessment helpsheets

If you鈥檙e the 鈥榩ersonal representative鈥� (an executor or administrator) for someone who has died, you might need to complete:

• a Self Assessment tax return for income the person earned before they died听
• a separate Self Assessment tax return for income the 鈥榚state鈥� generated after the person died

A personal representative is legally responsible for dealing with the deceased鈥檚 money, property and possessions (their estate).

Returns for income the person earned before they died

HMRC will tell you if you need to fill in a Self Assessment tax return for the person who has died. If you do, they鈥檒l send you a form to complete and return.

You鈥檒l usually need details of the deceased鈥檚 bank and savings accounts, for example:

• bank statements

• building society pass books

• dividend vouchers

• National Savings bonds or certificates

If the deceased was employed you鈥檒l usually need:

• a P45 from their employer - if the return is for the tax year they died听

• a P60 from their employer - if the return is for a tax year before the tax year they died

• details of any expenses paid by the employer - for example company cars, health insurance, travel expenses or childcare

If the deceased was receiving a pension you鈥檒l usually need:听

• a final statement from their pension provider - if the return is for the tax year they died

• an end of year certificate from their pension provider - if the return is for a tax year before the tax year they died

• confirmation of any state pension

You鈥檒l also need details of any other income they had, for example if they rented out property or ran their own business.

Sending the return

Send the completed Self Assessment form by post.听

The return must reach HMRC by the date given in the letter you received with the form.

You can hire a professional (such as an accountant) to help you submit a tax return on behalf of the deceased.

Returns for income the estate generated after the person died

If the estate generates any new income after the death, you may also need to do both of the following:听听

• register with HMRC听

• send a separate tax return on behalf of the estate

You must check if you need to tell HMRC about the estate鈥檚 income.