What bank reconciliation means
Bank reconciliation is the process of checking that the money in your books matches the money in your bank account. You take your bank statement for a period, usually a month, and compare it line by line with the income and expenses you have recorded. Every payment in should match an invoice marked as paid or a sale you recorded. Every payment out should match an expense, a bill, a tax payment or a transfer. When everything lines up, the closing balance in your books equals the closing balance on the statement, after allowing for anything still in transit. When it does not, the difference tells you that something is missing, duplicated or recorded with the wrong amount. It is the single most effective check you can run on your books.
Why do it if you have a banking app?
Your banking app tells you what happened in your account. It does not tell you whether your books are right. Without reconciliation, it is easy to end up with a profit and loss report that looks plausible but is quietly wrong: a client payment logged twice, a subscription you never recorded, a refund counted as new income. Those errors flow into your VAT return and tax return, and they are much harder to find a year later. Reconciliation also catches problems outside your books, such as a duplicate charge from a supplier, a payment you thought had been made but bounced, or a transaction you do not recognise at all. Ten to twenty minutes a month is a small price for books you can actually rely on.
What you need before you start
Gather three things. First, your bank statement for the month, downloaded as a PDF or CSV file from your online banking. Make sure it covers exactly the period you are checking, from the first day to the last. Second, your books for the same period: the list of recorded income and expenses, ideally in the tool you use for invoicing and bookkeeping. Third, the closing balance from your last reconciliation, which should be the opening balance on this month's statement. If this is your first time, pick a recent month-end, check that your books show the same balance as the bank on that date, and start from there. Do it for each business account and card separately; mixing them together makes differences much harder to trace.
The steps, one at a time
Start by checking that the opening balance on the statement matches the closing balance from last month's reconciliation. Then work through the statement from top to bottom. For each line, find the matching transaction in your books and mark both as matched. If a line on the statement has no match in your books, note it. When you reach the end of the statement, look the other way: are there transactions in your books for this month that do not appear on the statement? Note those too. You now have two short lists, items only in the bank and items only in your books. Work through each item, decide what caused it and fix it. When both lists are empty or fully explained, compare the two closing balances. They should agree.
Common differences and how to fix them
Most differences fall into a handful of types. Bank fees and interest appear on the statement but are often never recorded; add them as expenses or income. A client paid less than the invoice, perhaps because their bank took a transfer fee; record the payment at the actual amount and decide whether to treat the shortfall as a fee or chase it. A payment was recorded twice, often when you logged it manually and also imported it; delete the duplicate. An expense paid by card was never logged; add it, with the receipt. A transfer between your own accounts was recorded as income or an expense; reclassify it as a transfer, since it is neither. Timing differences, such as a payment made on the 31st that clears on the 2nd, are fine and simply carry over to next month.
A worked example
Say your books show a closing balance of €8,420 on 31 May, but the bank statement shows €8,150, a difference of €270. Working through the statement, you find a monthly bank fee of €12 that was never recorded and a €58 software subscription paid by card that you forgot to log. Looking the other way, you find a €400 client payment that you marked as received on 30 May, but which did not reach the bank until 2 June. And on the statement there is a €200 refund from a supplier that is not in your books. Add the €12 fee and €58 expense, record the €200 refund, and treat the €400 payment as in transit. Your books now show €8,550 and the bank €8,150, with €400 in transit explaining the gap exactly.
How often to reconcile
Monthly is the right rhythm for most small businesses. A month has few enough transactions that you still remember what each one was, and it fits naturally with sending a VAT return or reviewing your profit. If your business has a very high volume of transactions, or you are watching cash closely during a tight period, weekly reconciliation keeps problems even smaller. Leaving it for a whole year is where people get stuck: hundreds of lines, receipts that cannot be found, and payments nobody remembers. If you are behind, do not try to fix everything at once. Reconcile the most recent month first, so your current numbers are right, then work backwards one month at a time until you are caught up.
Lock the month when it matches
Once a month is reconciled, protect it. Many bookkeeping tools let you close a period, which stops anyone, including you, from adding, changing or deleting transactions dated before that point without deliberately reopening it. That matters because a single edited expense in a month you already reconciled breaks the match, and you might not notice until the next VAT return or year end. Reconciling and then locking each month gives you a clean history: every closed month matches the bank exactly, and any later correction goes into the current period with a clear note. This is also the natural last step of a month-end close, which brings invoicing, receivables, expenses and reconciliation together into one short routine.
Reconcile without the spreadsheet
You do not need to tick lines on a printed statement. Kelvo Books includes bank statement reconciliation: import your statement, match each line to the invoices, payments and expenses already in your books, and see straight away what is missing or duplicated. Invoices marked as paid, expenses logged from receipt photos and payments recorded through your @kelvo.app email address are all there to match against. When the month agrees, close the period so it stays that way, and your live profit and loss, cash flow and ledger reflect numbers you have checked. The free plan includes 10 invoices a month, unlimited clients and expenses, and the P&L. Pro at €7 a month adds unlimited invoices, reminders and recurring billing. Start at books.kelvo.app.