Self Assessment Tax Return

A tax-return is a form which has to be filed with HM Revenue and Customs declaring income during the tax year. This is because if you are self-employed, or a partner in business partnership you will not be registered through the normal channel of (Pay as You Earn) PAYE from an employer which declares your income on your behalf. 

First of all, it is important to understand what constitutes a tax year, as well as to note down some key yearly deadlines for Self Assessment and/or Small Business Tax Return.

A UK tax year runs from 6 April to the following 5 April, however when we talk about tax dates it is often described as either ‘during the tax year’ or ‘following the end of the tax year’. For example, if we talk about the 2023/24 tax year it would have started on 6 April 2023 and finishes on 5 April 2024, this means that 31 January during the tax year would be 31 January 2024, while for example the 31 January following the end of the tax year is 31 January 2025. 

When you file a tax return, it will always be for the last tax year.

Here are some key filing dates to remember;

5 October (following the end of the tax year) - You must notify HMRC by 5 October, if you did not submit a tax return for the previous tax year, but you need to submit one for the tax year that ended on 5 April, this is so that HMRC can send you a tax return.

31 October (following the end of the tax year) -  If you have not signed up for completing your tax return online you have to send HMRC a paper tax return by the 31 October. There are penalties if you send the form after this date, even if you have no tax to pay.

30 December (following the end of the tax year) - If you file your tax return online, you will need to submit it by this date if you want HMRC to collect your tax through your tax code. This may be possible where you owe less than £3,000. 

31 January (following the end of the tax year) - All online tax returns must be filed and submitted on or before this date, this includes any balance of payment due for that return. There are penalties if you miss this deadline for your return, even if you owe no tax or have already paid all of the tax you owe.

31 January (during the tax year) - You may have to make a payment on account by this date for the current tax year. For example, you may have a payment on account to pay for the 2020/21 tax year on 31 January 2021. Not everyone has to make payments of account.

April (after the end of the tax year) – As the tax year ends on 5 April, shortly after anyone who is required to file a tax return will receive a notice from HMRC advising them to file a tax return for the tax year which just ended. It is important to note you may still need to file a tax return even if you have not received a notice.

31 July (following the end of the tax year)- For those who make payment on account, the second payment for the tax year ending the previous 5 April is due. For example, the second payment on account for the 2019/20 tax year is due by 31 July 2020.

31 January (following the end of the tax year) + 1 year If you become aware that an entry on your paper or online tax return is incorrect you can amend that return up to 12 months after 31 January following the end of the tax year. For example, if you need to change your 2018/19 return you have until 31 January 2021 to make the amendments. This applies whether you filed using a paper return or completed it online.

First of all, if you have decided to take the plunge and become self-employed, then congratulations! 

Some people worry about setting up as self-employed or registering for a Director Tax Return, but registering with is fairly straightforward, and so here are the steps to follow to register with HMRC;

1. It is good to double check that your work counts as self-employment using the Employment Status for Tax

2. Then register for an online account with the online registration portal - gov.uk

3. You will then have to wait for your 10-digit Unique Taxpayer Reference (UTR) details to arrive by post

4. Using this reference, you can then complete your registration and set up your online account using the Government Gateway, which will ask for information about your business, like trading name and contact details. You will need to decide on a name for your business. Many people choose to trade under their own name, however if you choose a specific trading name, then make sure you double check that there aren't any other businesses using the same name

5. Once your online account is set up, it will give you access to a range of online government services, including completing your self-assessment tax return and making tax payments

If you miss the deadline for filing your return or paying the balance of your tax, then you will get a penalty. The initial late filling penalty is £100 if your tax return is up to 3 months late. You will have to pay more if it’s later or if you pay your balance late, and you will be charged interest on any late payments.  

To make it easier for your Accountant to process your tax return you will need to have to hand; 

• P60 – If you have paid any tax through PAYE or an employer, you should receive a P60 form. 

• Dividends received -  Dividends received from investments such as a portion of a company's earnings paid to you as a shareholder

• Bank interest – Any interest accrued on your bank or savings accounts

• P11D – Claims of expenses or benefits in kind 

• Pension contributions – Any pension contributions