The benefits of filing your self-assessment tax return today

The one good thing about the self-assessment tax return deadline is that it always remains the same – 31st January (when filing online). This means that with the help of your accountant and some organisation from yourself, you can avoid facing the penalties and stress of filing your tax return late or last-minute. In fact, a record 737,891 people filed their 2025/26 tax returns in April 2026.

Maintaining easily accessible and up-to-date records of your income and expenses throughout the year, means it will be easier for your tax return to be completed accurately and well before the deadline.

Here we explain why you shouldn’t delay in filing your self-assessment tax return. 

Won't I have to pay my tax bill early?

Filing your tax return early doesn't mean you have to pay your tax at the same time. You can wait until 31st January – the tax payment deadline does not change. Calculating your tax liabilities and filing your return now will allow you time to start budgeting and managing your cashflow ready to make your tax payment. You can plan for paying any tax you may owe by the 31st January deadline. 

Can I pay my tax through my tax code?

If you owe less than £3,000 in tax and file your tax return before 30th December you may be able to have your tax liability collected through your tax code. This means the self-assessment income tax you owe will be taken from your salary at source over a period of time and can be a great option to spread the cost of your tax bill over the rest of the tax year and ease the pressure on your cashflow.

Will I receive my tax refund from HMRC sooner?

Refunds of tax can arise for employees and directors due to issues with tax codes, periods of statutory pay such as maternity or paternity pay late in a tax year or a change in employment status. It is also not unusual for building subcontractors operating under the Construction Industry Scheme to receive tax refunds due the unique percentages of tax withheld by the lead contractor compared to the prevailing income tax rates.

The earlier you file your tax return, the sooner any refund will be paid to you. Don't wait until January to file your tax return, as you'll be waiting longer for your refund and missing out on any bank interest you would have received if the money had been sitting in your bank account.

What about penalties and late filing interest?

If you delay in filing your tax return, you risk missing the deadline and facing an automatic £100 filing penalty, no matter how much tax you had outstanding. If your tax return becomes more than three months late, £10 daily penalties will start building up until they hit a £900 peak. 

Should your tax return become more than six months late, then a penalty of the higher of £300 or 5% of your tax due will be charged. The same level of penalty is applied again if the return becomes over 12 months late. All of these penalties are in addition to one another and, as a result of this, the penalties for a late tax return could hit more than £1,600. 

From 6th April 2027 this penalty regime is set to change to a points-based system in line with the new Making Tax Digital (MTD) for income tax penalties. Under the points system, you would receive a point for a late return and after two points you receive a £200 penalty. 

When do I need to switch from self-assessment to Making Tax Digital for income tax? 

If you are a sole trader or landlord, you need to register for MTD for income tax and begin recording your income and expenses using MTD-compliant software when your qualifying income reaches specific thresholds: 

Tax year used for calculation	Qualifying income threshold	When MTD for income tax applies to you
2024/25	£50,000 or more	6th April 2026
2025/26	£30,000 or more	6th April 2027
2026/27	£20,000 or more	6th April 2028

For more MTD for income tax information, see our guide here. 

Why should I give myself plenty of time to prepare my tax return?

If your financial affairs changed this year, then putting them in order sooner rather than later will give you the time to think about any tax planning opportunities available to you. Apps like Dext make it much easier to keep track of all those receipts and invoices that build up over the months. Speeding through your tax return at the last minute increases the risk of mistakes being made. Giving you and your accountant time means your tax return will be correct and complete.

TaxAssist Accountants can help file your tax return

Tax has become an ever-changing and increasingly complex field and unless you have expert knowledge, you may be left bewildered and miss out on all the reliefs you are eligible for. Without the help of an advisor, you could end up paying too much tax without realising it, or accidently pay too little and risk an investigation or fines.

So why wait, call us today on 0208 441 6890 or use our simple online enquiry form and beat the deadline, be safe in the knowledge that you can be relaxed about your tax.

Last updated: 15th May 2026