Filing your 2025-26 self-assessment tax return

by Aitch, posted in Income Tax

The 2025–26 tax year ended on 5 April 2026, and attention now turns to filing your self-assessment tax return. While many leave this until the last minute, there are advantages to filing early.

There are two ways to file your return. You can submit a paper return, which must be filed by 31 October 2026, or file online, with a deadline of 31 January 2027. The 31 January deadline is also when any tax due for 2025–26 must be paid, along with the first payment on account for 2026–27.

Although the deadline may seem distant, preparing your return early can make a significant difference. Filing early does not accelerate the payment date, but it does give you certainty over how much tax you owe. This allows time to budget and set funds aside, avoiding pressure in January.

There are other benefits too. If you are due a refund, submitting early means you receive it sooner. It also gives more time to gather missing information, resolve queries, and avoid the last-minute rush when systems are busy and deadlines are tight.

In short, early preparation puts you in more control, whether that means planning for a future tax bill or importantly securing a repayment without delay.

Source:HM Revenue & Customs | 19-04-2026
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Aitch
I'm Aitch, the Founder and CEO of CIGMA Accounting Ltd. As a Chartered Management Accountant and as a CIMA member, I've spent more than 16 years helping businesses, entrepreneurs, landlords, and individuals with tax planning, accounting, and HMRC compliance. As a chartered accountant in London, I'm passionate about making complex tax matters easier to understand and helping clients make confident financial decisions. Over the years, I've advised start-ups, SMEs, established companies, and high-net-worth individuals across a wide range of tax and accounting matters. My expertise includes Corporation Tax, Self-Assessment, Capital Gains Tax, Inheritance Tax planning, R&D tax relief, capital allowances, international tax, and resolving complex HMRC compliance issues. Whether clients need a business accountant, tax accountant, or strategic tax advisor, my focus is always on delivering practical advice that creates long-term value. One of my specialist areas is Making Tax Digital (MTD). I've worked extensively with businesses preparing HMRC's digital reporting requirements, helping them move to cloud accounting, improve financial processes, and adopt technology that makes compliance more efficient. I regularly speak at Making Tax Digital roadshows, industry events, and educational sessions in collaboration with Zoho Books, sharing practical insights into digital accounting, tax legislation, and the future of the profession. Many business owners looking for the best accounting firm in London are not simply searching for an accountant they're looking for trusted advice, responsive support, and long-term value. That's the approach I've taken in building CIGMA Accounting. My team and I work closely with businesses across London and the UK, providing accounting services, tax advisory, bookkeeping, payroll, VAT, company accounts, and strategic tax planning tailored to each client's goals. Through this website, I share practical guidance on UK taxation, Making Tax Digital, HMRC updates, Corporation Tax, Self-Assessment, and business finance. My aim is to provide reliable, straightforward information that helps business owners understand changing regulations, reduce compliance risks, and make informed financial decisions with confidence.
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