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Posted: Tue 18th Aug 2026
A simple bookkeeping system gives you a clear view of what's happening in your business.
You can see what customers owe, what bills are coming up, how much tax you may need to pay and whether sales are turning into usable cash.
That's important in London, where rent, transport, storage, staffing and supplier costs can quickly eat into a healthy-looking bank balance.
You don't need a complicated set-up from the start – just some reliable records and a routine that still works when you get busy.
Bookkeeping is the process of recording and organising the money moving through your business. That covers:
Sales.
Customer payments.
Purchases.
Refunds.
Bank charges.
Loans.
Money you put into or take out of the business.
You record each transaction with enough detail to show what happened, when it happened and what it related to.
You or your accountant (if you have one) then use those records to prepare accounts, calculate tax, assess how the business is performing and support bigger financial decisions.
A bookkeeper keeps the underlying information accurate and up to date. An accountant works with that information.
The distinction is good to know, though the roles often overlap. Some accountants offer bookkeeping services and some bookkeepers help with VAT returns, payroll and management reports.
Most businesses need to keep track of the same basic areas.
Record all income, including sales, fees, commission and any other payments the business receives.
For each sale, note the date, customer, amount, payment method and VAT charged (where relevant).
Keep copies of invoices, online order records, till reports and statements for any payment platforms you use.
Take care with platforms that deduct fees before transferring money to you.
Suppose a customer pays £100 and the platform sends £96 to your bank after taking a £4 fee. Your records should show £100 of income and a £4 cost. Recording only the £96 understates both figures.
You must also record refunds properly. Don't just delete the original sale, as you need a clear record of what happened.
Record the money the business spends. This includes money towards premises, stock, materials, software, insurance, marketing, travel or professional fees.
Keep the receipt or supplier invoice and add a short note if the business purpose isn't obvious. A £48 payment to a restaurant, for example, could be a client meeting or a personal meal. The bank statement alone won't tell you.
A payment from the business account isn't automatically an allowable business expense for tax purposes. The cost must normally relate to the business.
Where something has both business and personal use, you can usually claim only the business share.
Sales invoices show what you charged a customer. Supplier invoices show what another business charged you. Receipts confirm that payment was made.
Number your sales invoices consistently. Include the correct customer details, issue date, amount, payment terms and VAT information (where relevant).
When you've made a purchase, save all documents as soon as you receive them.
Paper receipts fade, get damaged and disappear. Photographing or scanning them takes seconds and makes them much easier to find later.
Your bookkeeping records should explain every transaction on your business bank account or card. This includes:
Card payments.
Direct debits.
Bank charges.
Cash withdrawals.
Transfers between accounts.
You must record transfers carefully so they aren't mistaken for income or spending.
Some payments may need splitting. A loan repayment can contain both capital and interest. Only the interest is normally treated as an expense in the usual way.
You must normally register for VAT when your taxable turnover goes above £90,000 during a rolling 12-month period.
You may also need to register if you expect to exceed the threshold within the next 30 days.
Once registered, you need to record the VAT charged on sales and the VAT paid on purchases.
Most VAT-registered businesses must keep certain records digitally and submit returns using compatible software under Making Tax Digital.
It isn't always obvious what VAT rate you should use. Deposits, imports, exports and mixed supplies can all make things more complicated.
Check the rules or ask a professional for advice rather than guessing which rate applies.
If you're a new business with a small number of transactions, no employees and no VAT registration, a spreadsheet may be enough for your bookkeeping.
At the very least, it should show:
Sales and other income.
Business expenses.
Customer invoices yet to be paid.
VAT, if relevant.
The category and date of each transaction.
Spreadsheets are cheap to compile, but they do take time. Plus there's the risk of formulas breaking, transactions being entered twice, and delays with reconciling records with the bank.
Luckily, there are accounting software tools you can use.
They can import bank transactions, create invoices, attach receipts and produce reports. They can also make it easier to share information with a bookkeeper or an accountant.
Since 6 April 2026, Making Tax Digital for Income Tax has applied to some sole traders and landlords with qualifying income above £50,000. That £50,000 threshold is due to fall to £30,000 from April 2027 and £20,000 from April 2028.
When choosing accounting software, check whether it works with your bank, payment processor or online shop.
A cheap platform that doesn't connect to the tools you already use may generate more work.
Keep your categories simple to begin with. Common categories include stock, premises, marketing, software, travel, insurance and professional fees.
Add more detail only when it helps you understand the business or complete a tax return.
Too many categories can confuse matters. You don't need separate headings for every type of stationery unless that level of detail is useful to know.
Open a separate bank account for business transactions and use it consistently.
This is particularly important if you're a limited company. Limited companies are separate legal entities from their owners, so company money must be treated carefully.
That said, a separate business account will help if you're a sole trader, as it cuts down on admin and makes errors easier to spot.
Try not to pay personal costs from the business account or business costs from your personal account. If you can't avoid it, record the transaction properly. Don't leave it unexplained.
The same principle applies to business credit cards, payment apps and savings accounts. The more clearly you separate your money, the easier the books will be to manage.
Choose one place for digital records and stick to it.
A straightforward folder structure organised by year and month will work for many businesses. Use file names that tell you what the document is, such as "2026-07 supplier name £145 invoice".
Some software lets you attach receipts directly to transactions. This saves time when you or your accountant need to check the details later.
Back up important records and make sure the right people can access them. Avoid storing everything in one person's inbox or on a laptop that no-one else can open.
Under HMRC rules, self-employed people must keep records for at least five years after the relevant 31 January tax return deadline.
Different rules apply to limited companies and VAT records, so check what applies to your business.
Bookkeeping works best when it becomes a regular job rather than a rescue operation.
For many small businesses, a weekly update and a fuller monthly review are enough.
During the weekly session, record income and spending, upload receipts, send invoices and check whether any customers have missed their payment date.
Move money aside for tax and VAT as you go.
At the end of each month, reconcile your accounts. Reconciliation means comparing your bookkeeping records with bank and card statements to make sure the figures match.
Look for missing transactions, duplicates and payments in the wrong category. Match customer payments to the correct invoices and investigate anything you don't recognise.
Bank feeds help, but you must still check your records. Software can see that £82 left the account, but it can't always tell whether it was stock, travel, a personal payment or a transfer.
Keep an eye on unpaid invoices too. Record when each invoice was sent, when it's due and what follow-up has taken place.
Send reminders soon after the due date rather than waiting until several invoices have built up.
And set aside tax while the money is available. A separate savings account can help you avoid spending cash that you'll later need for Self Assessment, Corporation Tax or VAT.
Mixing personal and business spending. This makes your records harder to check. It can also cause you to file incorrect expense claims or miscalculate payments to directors or owners.
Leaving bookkeeping for several months. You may no longer remember what a payment was for, or whether you received a receipt. Consequently, bookkeeping becomes slower and your records become less reliable.
Misclassifying costs can affect tax and financial reports. You may record equipment as a routine office expense, treat loan payments as ordinary spending or label money taken by a director as wages.
Losing receipts. Do this and you might miss a valid expense or have nothing to support a claim. A bank statement proves that money changed hands but may not show what you bought.
Relying on your bank balance as a complete picture of the business. It doesn't show unpaid bills, overdue customer invoices, future tax or stock you've already ordered.
Managing your own books can work well while the business is small and the transactions are straightforward.
You might need to consider professional support when you start selling more, become liable for VAT or can't work out what tax applies to certain transactions.
You may also need help if you take on employees, sell overseas, use several payment platforms or start carrying stock.
A bookkeeper will usually handle regular financial records. They can enter transactions, process receipts, reconcile bank accounts, track invoices and help with VAT returns.
An accountant generally handles annual accounts, tax returns, tax planning and advice on business structure. They may also help you interpret the figures and plan for growth.
Ask them clearly what their service includes. Find out how often they'll update your records, when you need to send documents and who deals with VAT, payroll or late invoices.
Outsourcing the work doesn't mean ignoring it. You should still review the numbers, understand what the business owes and know when payments are due.
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