Self-assessment tips: how to successfully complete your tax returns

Our dedicated tax team has provided their top 10 tips and reminders to help make your tax return less stressful.

Tip 1: Before proceeding, check whether you are required to submit a self-assessment tax return for the tax year 2022/23

It is not always necessary to complete a tax return to pay tax on untaxed income. You can check if you need to file a self-assessment return at https://www.gov.uk/check-if-you-need-tax-return. If a tax return is not required, HMRC will still need to be told about any tax due and you will need to arrange for this to be collected or paid.

Tip 2: Don’t miss the deadline!

Allow enough time to gather everything you need to file your self-assessment tax return. The most important thing to remember when filing a self-assessment tax return is the deadline, which is:

31 October following the end of the tax year for a paper return.

31 January following the end of the tax year for an online return.

The tax return will need to be filed online as the deadline to file a paper return for 2022/23 was 31 October 2023.  To do so, you will need a government gateway account, if you do not already have one, and the process to register for this can take about 10 days. Failing to file or pay on time will generate penalties and late payment interest charges. Technically the date to let HMRC know you needed to file a return was 5 October 2023, but if all the tax is paid by the due date, then HMRC are less likely to impose a penalty for late notification.

Tip 3: Don’t forget that the changes to the dividend allowance may impact you

The dividend allowance, the band in which dividend income is taxed at 0%, was £2,000 for 2022/23. If, when added to your other taxable income, your dividend income takes you over the personal allowance and the dividend income is over £2,000, you will need to let HMRC know as tax will be due. The dividend rates are 8.75% for basic rate taxpayers, 33.75% for higher rate taxpayer and 39.35% for additional rate taxpayers.

Note that for the 2023/24 financial year, the tax free dividend allowance was halved from £2,000 in 2022/23 to £1,000. This means that any individual that receives over £1,000 in dividend income in the 2023/24 financial year will be liable to pay dividend tax on the excess at their marginal rate. The dividend allowance will be reducing further to £500 for 2024/25.

Tip 4: Remember that you have the option to amend your PAYE code in order to collect tax in the coming year

It can be possible to receive up to £10,000 of dividend and investment income without the need to file a tax return. If tax is due, contact the HMRC (HM Revenue and Customs) helpline and ask them to change your PAYE code to collect the tax over the next year from your wages or pension. If this is not possible, you will need to pay HMRC by 31 January 2024 to avoid late payment penalties.

Tip 5: Check the details on capital gains tax

Capital gains tax is applicable to profits you make from selling or disposing of an asset, for example a buy to let property or other assets of value.

For the 2022/23 tax year, any gains over the capital gains tax annual exemption of £12,300 for 2022/23 or proceeds over £49,200, will need to be reported on your tax return. If you have not been issued with a tax return, but have reportable gains or proceeds, you will need to let HMRC know.  You can do this by using the HMRC real time information service.

If you have sold a UK residential property, the gains and tax liability should be reported and paid to HMRC on the Report and Pay your Capital Gains Tax system within 60 days from completion of the sale.

As part of the government's budget in October 2022, the capital gains tax allowance was reduced by 50% for 2023/24 to £6,000 and will further reduce to £3,000 for 2024/25.  The capital gains reporting limit is now set at £50,000.

Tip 6: Make sure to use up all of your allowable expenses

When looking at your tax position, don’t forget to claim reliefs and allowances that are available. These include personal pension contributions paid by higher rate tax payers, charity donations, and the marriage allowance if one of a couple earns below the personal allowance and the other spouse/civil partner is a basic rate taxpayer.  Sometimes you may also be able to claim relief for professional memberships where these are not paid by an employer.

Tip 7: If you have been issued with a return, don’t ignore it!

If HMRC have issued you with a return, even if you have no untaxed income or tax due, you will need to file the return or HMRC will issue a penalty. You can contact HMRC to explain your circumstances and they may withdraw the return, which will remove any penalties charged. However, HMRC can insist the return is filed so they can review your tax position.

Tip 8: Beware of estimations in P800 calculations and Simple Assessments and get them corrected

HMRC may have removed you from self-assessment and instead issued you a Simple Assessment, or, if you receive pension or salary, issue you with a P800 calculation. These are the HMRC’s calculation of your tax position for the year. You will need to check them, particularly if you have income other than state pension, other pension or employment income, as HMRC may have estimated your other income figures.

You may get a Simple Assessment letter from HMRC if you:

• owe Income Tax that cannot be automatically taken out of your income
• owe HMRC £3,000 or more
• have to pay tax on the State Pension

If the figures are wrong, you will need to contact HMRC and get these corrected. Any tax payable under the Simple Assessment regime for the  2022/23 tax year is due by 31 January 2024 or within 3 months of the issue date if you got your letter after 31 October.

Tip 9: Use this time to check if you are due back overpaid tax

The tax deadline is not just about ensuring you are paying what you owe. It is also an opportunity to see if you are owed money back. You don’t need to complete a tax return to get back overpaid tax. This can also be done by submitting a form R40 or contacting HMRC.

Tip 10: Most importantly, if you are unsure, then seek advice

Navigating tax rules isn’t easy. If you have any questions or concerns, don’t hesitate to speak to your financial adviser who is here to help you.