Do you need to submit a self-assessment tax return by the end of January 2026?

CREATED BY ALISON MEAD Published: 11/01/2026 @ 09:00AM #self-assessmenttaxreturn #SelfAssessment #HMRC #TradingAllowance #SideHustle #UKTax

Wondering if a self-assessment tax return is due by the end of January 2026? This explains who typically needs to file, how the £1,000 trading allowance fits around the 5th of April, and why HMRC may still expect a return if someone registered or filed before ...

Self-assessment tax return, Numbers and forms to fill, An annual task?

Most people only need to file a self-assessment tax return when there's a clear reason HMRC expects one, and it usually comes down to what happened in the tax year that ended on the previous 5th of April. The simplest way to think about it is that HMRC cares about what was earned in that tax year, and whether the person's circumstances mean a return is required.

For many side hustles, the £1,000 trading
allowance is the pivot point!

If someone's total trading income for the tax year to the 5th of April 2025 went over £1,000, that commonly puts them into self-assessment territory for that year, and a self-assessment tax return may be needed by the January 2026 deadline.

The timing around the tax year-end matters more than people expect. If someone started selling, freelancing, or creating content before the 5th of April 2025, but did not exceed the £1,000 trading allowance by that date, they generally won't be counting that same income again in the next tax year; from the 6th of April 2025 it's a fresh tax year, so the running total effectively starts again for measuring what happens in 2025/26.

Where it gets less forgiving is registration. If someone registered for self-employment and told HMRC their business started before the 5th of April 2025, HMRC may still expect a self-assessment tax return for that year even if the person later paused, gave up, or earned less than expected.

The logic is straightforward: registration signals to HMRC that there is a business to report, and HMRC systems often continue to expect a return until the position is formally updated.

The same 'expectation' issue crops up for people who have filed before. If someone has been in self-assessment previously, HMRC may continue to issue filing requirements year after year unless the person has specifically told HMRC they no longer need to submit returns.In practice, that means someone can be below the trading allowance and still be chased for a self-assessment tax return simply because their record still says they're in the system.

For anyone who is unsure whether they crossed the £1,000 line, or just wants to avoid guesswork, good records tend to resolve the question quickly. A simple spreadsheet that logs income and expenses can make it obvious whether a self-assessment tax return is needed, and it can include optional sections for more niche situations, such as TikTok affiliates receiving gifted samples, which can be ignored if it's not relevant.

Ultimately, the January deadline is only stressful when someone waits for certainty to appear on its own!

If they check what was earned up to the 5th of April 2025, confirm whether they registered (or are still registered) for self-employment, and make sure HMRC isn't still expecting filings from previous years, they'll know whether a self-assessment tax return needs to be submitted by the end of January 2026.

Please note: If you are unsure of your numbers, I have a spreadsheet for self-employment side hustles that you can download to verify. It includes an area for TikTok affiliates who get samples, though you can ignore that page if not needed.

Click here to visit Payhip and discover more.

Until next time ...

ALISON MEAD
I'm your Bookkeeping Buddy: Discover more by clicking here!

Share the blog love ...

Buffer Facebook Twitter Linkedin Pinterest WhatsApp #self-assessmenttaxreturn #SelfAssessment #HMRC #TradingAllowance #SideHustle #UKTax

About Alison Mead ...
Alison loves bookkeeping and supporting bookkeepers. She has been helping clients to be better bookkeepers in Sage 50 for over 24 years and has been Xero Accredited in accounts and payroll for a number of years too. She specialises in a very unique hand-holding method of training, helping bookkeepers and business owners to use their accounts software as and when they need support in setting up and producing their invoices, reports and financial information. Alison combines her role at Silicon Bullet with her Forever Living network marketing businesses and is often to be seen at business networking meetings as she likes to keep busy. You know what they say: if you want something done well ask a busy person!

More blog posts for you to enjoy ...
		The real costs of starting a bookkeeping business: Part 1 Here's what you'll actually pay for when you're new. I'll walk through the real costs of starting a bookkeeping business, focusing on the non-negotiables. You'll finish with a clearer budget and fewer surprises ......
		Sage version 33 released: smarter, smoother, and future-ready Here's more information about the Sage version 33 release. It's about reducing admin and tightening compliance. Expect cleaner email management, better VAT handling across the UK and Ireland, and improved AI document capture....
		Making Tax Digital for the self-employed: thresholds, quarterly updates, and ways to stay calm Making Tax Digital for the self-employed will change how many sole traders and landlords handle income tax reporting. It's quarterly updates plus a year-end declaration, built from your digital tax records in MTD software. Th...
		Why Should You Use A Bookkeeper? Keeping track of your accounts is a science as well as an art form. Yes, of course you can do it yourself, but wouldn't a bookkeeper make your life a whole lot easier? Having a clear picture of your finances at any given time...
		Some Great Reviews For My Bookkeeping Buddy Subscription Do It Yourself bookkeeping often feels like a chore when you're managing your own business accounts or even just starting off as a bookkeeper. This is why I created by Bookkeeping Buddy subscription and I'm getting some great...
		Building Your Bookkeeping Business in 2026 The usual question I see asked in bookkeeping groups and forums is, where can I find customers, or how can I get experience now that I have passed my bookkeeping exams and started my bookkeeping business ......
		Sage 50 Accounts and Payroll subscription changes Here's the Sage 50 accounts and payroll subscription changes in plain English. Direct prices rose earlier, partner-billed rises land later. Learn how timing and route to purchase affect your bill ......
		Why side hustlers should try the Etsy app for Xero today The Etsy app for Xero helps side hustlers automate sales, fees, and taxes, cutting administration and accounting errors. It turns messy payouts into clear records. It's a smart, simple boost for your bookkeeping ......

Other bloggers you may like ...
		Chatbots for web designers and marketing agencies Posted by Steffi Lewis on https://www.yourbot.uk If you run a web design studio or a marketing agency, you already know what your clients want. They don't care about tokens, APIs, or the number of la ...
		Cybersecurity tips for protecting your business, family and personal data Posted by Roger Eddowes on https://blog.essendonaccounts.co.uk Here are some cybersecurity tips you can actually use day to day, without getting overwhelmed. Learn how to spot common scams, verify requests safely, ...
		Renovating your home in Milton Keynes? Come and stay with us! Posted by Emily Freeman on https://blog.shortstay-mk.co.uk Renovating your home can be loud, messy, and surprisingly draining. You can sidestep the chaos by staying somewhere local that feels settled, private, ...
		What is the career landscape like right now? Posted by Dave Cordle on https://blog.davecordle.co.uk So, what is the career landscape like right now? It's faster, more flexible, and more skills-driven than it used to be. You'll do best by translating ...