We are once again staring down the barrel of the self-assessment tax return deadline.
If you are one of the 5.65 million people who entered 2026 with your self-assessment tax return unfiled, then you are running out of time.
Even as the deadline looms, it is best that you understand what you should be doing so you can avoid costly mistakes.
What do I need to do before the self-assessment tax return deadline?
While it might seem like the answer is to simply file your self-assessment tax return, there may be a reason why you have delayed doing so for so long.
One reason why some people delay filing their self-assessment tax returns is that they do not understand what needs to be included and are scared of getting it wrong.
It is possible to file a self-assessment tax return once the tax year ends and the returns we are currently filing for clients relate to the 2024-2025 tax year.
As such, you will have to go back through your financial records to ensure that you can accurately capture all the figures that need to be declared.
As well as the money you have earned as a sole trader, self-employed individual and/or landlord, you should also include any side hustles.
Even if these are as small as making and selling artwork online or getting paid to walk the neighbourhood dogs, you need to declare this income.
If these earnings are below £1,000, then you will not need to register for self-assessment simply to handle them, but anything above that would require a self-assessment tax return, even if you were employed by a company as your main income.
For those already filing self-assessment tax returns, side hustles need to be included so that the additional income can be added to the other figures you are declaring.
Your self-assessment tax return is not all doom and gloom, as you can declare things like charitable donations and other expenses.
These can help to ease the burden of your tax bill, with business expenses being particularly useful for freelancers and self-employed individuals.
How can I avoid this stress next year?
For some of you, Making Tax Digital (MTD) for Income Tax will decrease the chance of running late with filings again.
For sole traders, landlords and self-employed individuals with incomes over £50,000, April 2026 will see MTD become mandatory.
The threshold drops to £30,000 in 2027 and £20,000 in 2028, so more people will be pulled in over time.
If you are going to be impacted by MTD, then you will be subject to quarterly filings with a final annual submission for old time’s sake.
The aim of MTD, according to the government, is to reduce tax ‘leakage’ through error and fraud, as well as help taxpayers have a better connection with their finances, so submitting tax returns feels less daunting at the end of the year.
Whether it will achieve this remains to be seen, but from 2027, there will be more penalties for missing deadlines.
Anyone not impacted by MTD should learn from this year’s stress.
Submitting your self-assessment tax returns as close to the end of the tax year as possible means you do not have the stress hanging over you all year like a fiscal Sword of Damocles.
A new tax year is a good opportunity to reset your finances and get into better habits.
