Small business bookkeeping means keeping a complete, dated record of every penny that comes into and goes out of your business. At a minimum, UK law requires you to record all sales and income, all business expenses and purchases, VAT (if registered), PAYE records (if you employ staff), and what you personally take out of or put into the business. You must keep the supporting proof, invoices, receipts and bank statements, for at least five years.
Get this right and your Self Assessment or company accounts almost write themselves. Get it wrong and you risk overpaying tax, missing deadlines, or facing penalties if HMRC asks to see your records.
What Records Must a Small Business Keep?
Whether you are a sole trader or a limited company, your bookkeeping must capture enough detail to work out your profit or loss and prove every figure on your tax return. The core records are:
| Record | What to keep | Why it matters |
|---|---|---|
| Sales & income | Invoices raised, till rolls, sales receipts, PayPal/Stripe statements | Forms your turnover, the basis of your tax |
| Purchases & expenses | Receipts, supplier invoices, expense claims | Reduces taxable profit; must be "wholly and exclusively" for business |
| Bank & card statements | Business account statements, chequebook stubs, paying-in slips | Cross-checks income and spending |
| VAT records | VAT invoices, a VAT account | Required once registered (see below) |
| PAYE/payroll | Pay, deductions, P60s, P11Ds | Required if you employ anyone (including yourself via a company) |
| Assets | Purchase records for equipment, vehicles, computers | Needed to claim capital allowances |
| Drawings/dividends | Money you take out personally | Keeps business and personal money separate |
You also need to record amounts you have committed to but not yet paid (for example, an unpaid supplier invoice) and the value of any stock and work in progress at your year end.
Sole Trader vs Limited Company Record-Keeping
A sole trader keeps records to complete the self-employment pages of their Self Assessment. A limited company has stricter duties: it must keep formal accounting records, a register of shareholders and directors, and file accounts at Companies House as well as a Corporation Tax return with HMRC. The day-to-day bookkeeping is the same for both, though, record everything, keep the proof.
How Long Must You Keep Business Records?
If you are self-employed, you must keep your records for at least five years after the 31 January Self Assessment deadline for that tax year. So records for 2026/27 (filing deadline 31 January 2028) must be kept until at least 31 January 2033.
Limited companies must keep records for six years from the end of the company's financial year, longer if a transaction spans more than one accounting period or relates to an asset expected to last several years. HMRC's official guidance on business records if you're self-employed sets out what counts as acceptable proof.
Paper or Digital Records, Does It Matter?
No format is mandatory: you can keep records on paper, digitally, or inside bookkeeping software. In practice, digital wins. Making Tax Digital (MTD) for Income Tax is being phased in for sole traders and landlords with qualifying income over £50,000 from April 2026, and over £30,000 from April 2027, affected businesses must keep digital records and submit quarterly updates. Even if you are below the threshold, cloud bookkeeping software saves hours and reduces errors. See our bookkeeping services if you would rather hand the whole thing over.
Key 2026/27 Figures Every Small Business Should Know
These thresholds shape what you record and when you must register:
| Figure | 2026/27 |
|---|---|
| VAT registration threshold | £90,000 turnover (rolling 12 months) |
| Personal allowance | £12,570 |
| Higher-rate threshold | £50,270 |
| Additional-rate threshold | £125,140 |
| Trading allowance | £1,000 |
| Dividend allowance | £500 |
| Annual Investment Allowance | £1,000,000 |
| Business mileage (cars) | 55p first 10,000 miles, 25p thereafter |
| Electric company car BiK rate | 4% |
If your taxable turnover passes £90,000 in any rolling 12-month period, you must register for VAT, accurate bookkeeping is the only way to spot this in time. The £1,000 trading allowance means very small side incomes may not need full accounts, but keeping records is still wise.
A Simple Bookkeeping Routine for Beginners
You do not need to be an accountant to stay on top of this:
- Open a separate business bank account. It makes every other step easier.
- Capture receipts as you go, photograph them; do not rely on memory.
- Reconcile weekly or monthly, match transactions to your bank statement.
- Set money aside for tax, a rough 20-30% of profit is a sensible buffer.
- Review your numbers quarterly so there are no surprises at year end.
Frequently Asked Questions
Do I need bookkeeping software for a small business?
No, it is not legally required, a spreadsheet can be enough for a very small sole trader. But software cuts errors, speeds up Self Assessment, and becomes effectively essential once Making Tax Digital applies to you. Most businesses find the time saved easily justifies the cost.
What happens if I do not keep proper records?
HMRC can charge penalties of up to £3,000 for failing to keep adequate records, and without proof you cannot reliably claim expenses, so you may overpay tax. If HMRC opens an enquiry and you cannot evidence your figures, they can estimate your tax and add interest and penalties.
Can I do my own bookkeeping?
Yes. Many sole traders manage their own books successfully, especially with cloud software. As you grow, take on staff, register for VAT or incorporate, the admin grows too, that is usually the point most owners bring in a bookkeeper. Our FAQ page covers when it is worth outsourcing.
Do I need to keep paper receipts if I have digital copies?
No. HMRC accepts digital copies of most records as long as they are legible and complete, so you can scan or photograph receipts and bin the paper. The exception is anything showing tax that cannot be replaced from another source, keep those safe.
Sound bookkeeping is the foundation of a tax-efficient, stress-free business, and far easier to keep on top of than to fix in a panic each January. If you would like a hand setting up a simple, HMRC-ready system, or want to hand the books over entirely, get in touch with Zmartly and we will sort it for you.
