If you have just registered for Self Assessment, your first return probably feels a long way off. January always is — until it suddenly is not. The single biggest difference between a stress-free tax return and a January scramble is not intelligence or luck. It is the records you start keeping today.
The good news? Good record-keeping is a habit, not a talent. Here is exactly what to keep, how long to keep it, and how to make it almost effortless.
Why record-keeping matters more than you think
When you are self-employed — as a sole trader or in a partnership — HM Revenue & Customs (HMRC) expects you to keep records of your business income and expenses for your Self Assessment return, along with records of your personal income. HMRC can check your records to make sure you are paying the right amount of tax, and if you cannot back up the figures on your return, you could face penalties on top of any extra tax.
There is an upside, too. Well-kept records mean you can claim every expense you are genuinely entitled to — from stock and software to travel and a portion of your home costs. Missing receipts usually mean missed deductions, and missed deductions mean paying more tax than you need to.
The records you actually need to keep
You do not need a filing cabinet full of paper. You need a complete, accurate picture of money in and money out. At minimum, hold on to:
- Sales and income records — invoices you have issued, and records of any other income, including cash payments
- Expense receipts — for everything you buy for the business, from equipment to postage
- Bank statements — for your business account (and personal account if you mix them)
- Mileage or vehicle records — if you claim for business travel
- Personal income records — payslips, P45s or P60s from any employment, pension statements and bank interest summaries
- Grant or support payments — most grants count as taxable income, so keep the paperwork
A useful rule of thumb: if a figure on your tax return would change without a document, keep that document.
Good records are not about paperwork for its own sake — they are how you pay the right amount of tax. No more, no less.
How long do you need to keep your records?
HMRC’s rule is simple: keep your records for at least 5 years after the 31 January submission deadline of the relevant tax year. So if you file your 2024–25 tax return online by 31 January 2026, you must keep the supporting records until at least the end of January 2031.
If you file a return very late — more than 4 years after the deadline — you will need to keep your records for 15 months after you send it instead. And if records are lost, stolen or destroyed and you cannot replace them, do your best to provide figures, then tell HMRC when you file whether you are using estimated or provisional figures.
Cash basis or traditional accounting?
One decision shapes what you record and when. From the 2024–25 tax year, cash basis is the default accounting method for sole traders and partnerships. With cash basis, you only record income when you actually receive it and expenses when you actually pay them — so you never pay Income Tax on money that has not arrived yet. If you prefer traditional accounting (recording invoices as they are issued), you must actively opt out.
Cash basis suits most small businesses because it mirrors what is actually in your bank account, which makes record-keeping simpler. A handful of situations — such as wanting to claim certain reliefs — may make traditional accounting the better fit, so it is worth taking advice before you lock in your choice.
Simple habits that make January painless
The beginners who breeze through their first return almost always share the same habits:
- Separate your money. A dedicated business bank account makes income and expenses obvious at a glance.
- Snap receipts as you go. Photograph them weekly — not in a January panic.
- Reconcile monthly. Ten minutes comparing your records to your bank statement catches problems while they are small.
- Use software or a simple spreadsheet. Digital records are easier to search, back up and share with an accountant.
- Diary the deadlines. Online returns are due by 31 January following the tax year (6 April to 5 April).
One change is coming that makes digital record-keeping essential: from April 2026, Making Tax Digital for Income Tax applies to self-employed people and landlords with qualifying income over £50,000, who will need to keep digital records and update HMRC quarterly. Starting digitally now means that transition will be seamless rather than stressful.
Quick answers
Do I still need to keep paper receipts?
No. Digital copies — a clear photo or a scanned image — are fine, as long as they are legible and capture the key details. Many small business owners never touch paper at all.
What if I have lost some of my records?
Do your best to provide figures and tell HMRC on your return whether you are using estimated or provisional figures. Then put a system in place so it does not happen again.
How long must I keep my Self Assessment records?
At least 5 years after the 31 January submission deadline of the relevant tax year. Filing late by more than 4 years? Keep records for 15 months after sending the return instead.
Do I legally need a business bank account?
Not if you are a sole trader, but separating your money makes record-keeping dramatically easier and looks more professional to banks and lenders.
When is the Self Assessment deadline?
Online returns are due by 31 January following the end of the tax year (6 April to 5 April). Paper returns must be filed by 31 October.
Need a hand with your records?
You did not go self-employed to spend evenings sorting receipts. At Taxora Accountancy, a dedicated personal accountant can take bookkeeping, Self Assessment and tax planning off your plate, with fixed monthly fees from £9.99 and unlimited support along the way. Get in touch today or browse our services and prices — and make next January the easiest one yet.
This article is general information only and does not constitute financial, tax or accounting advice. Tax rules can change, and the right approach depends on your circumstances — please speak to a qualified accountant before acting.