Bank reconciliation is the process of matching the cash balance in your own records against the balance your bank statement shows, then explaining every difference between them. You line up your books next to the statement, tick off everything that appears on both, and account for what only appears on one side — a check that hasn't cleared, a deposit the bank hasn't posted, a fee you didn't record. When both sides are adjusted and finally agree, the account is reconciled and you can trust your cash balance.
It matters because the two numbers almost never match on the first look, and that's normal. Your books and the bank are keeping the same account from two angles, with a timing lag between them. Reconciliation is how you turn "the balances are different" into "the balances are different for these specific, explained reasons" — and how you catch the ones that aren't innocent, like a bank error or a fraudulent charge. This guide covers the formula, the step-by-step process, two worked examples, and the mistakes that trip people up.
To reconcile two records is to make them agree. In accounting, a bank reconciliation is the specific job of comparing the cash balance in your books — your ledger, your accounting app, or your spreadsheet — with the balance on the statement from your bank, and confirming the two can be brought into agreement once you account for timing and unrecorded items.
Here's the plain version. You keep a running record of your cash: every deposit adds to it, every check and withdrawal subtracts. The bank keeps its own record of the exact same account. In a perfect world the two would always show the same number. They don't, because things hit each record at different times. You mail a check today and record it today; the vendor deposits it two weeks later, so the bank doesn't subtract it until then. The bank charges a monthly fee you won't see until the statement arrives. A customer's check bounces after you already counted it as cash.
Reconciliation lines the two records up and answers one question for every difference: why? Once every gap has a reason, and the adjusted balances match, you know your books are right. If a gap has no good reason, you've found something worth chasing — a data-entry mistake, a bank error, or unauthorized activity on the account.
Reconciling isn't busywork. It's one of the simplest and strongest internal controls a small business has.
Reconciliation works on two balances, and you adjust each one separately until they meet in the middle.
Adjusted bank balance = bank statement balance + deposits in transit − outstanding checks
Adjusted book balance = your book balance + interest and credits the bank added − bank fees, NSF charges, and other deductions you hadn't recorded
The goal is simple: adjusted bank balance = adjusted book balance. When those two numbers are equal, the account is reconciled. The Corporate Finance Institute frames it the same way — you fix the bank side for timing items and the book side for items you didn't know about yet, and the two land on the same true figure.
Notice the split. Timing items (deposits and checks the bank hasn't processed) get adjusted on the bank side, because your books are already right and the bank just needs to catch up. Unrecorded items (fees, interest, bounced checks) get adjusted on the book side, because the bank is right and your books need to catch up. Knowing which side an item belongs on is most of the skill.
Nearly every gap between your books and the bank comes from this short list.
1. Get both records for the same period. Pull your bank statement (say, for August) and your own book balance as of the statement's closing date. Reconcile like-for-like periods, or nothing will line up.
2. Match what appears on both. Go line by line and tick off every transaction that shows up in your books and on the statement — cleared deposits, cleared checks, cleared card payments. These agree; set them aside.
3. List what's on only one side. Whatever's left is your reason list. Deposits and checks that are in your books but not on the statement (timing items). Fees, interest, and NSF reversals that are on the statement but not in your books (unrecorded items).
4. Adjust the bank balance. Start from the statement's ending balance. Add your deposits in transit; subtract your outstanding checks. This is what the bank balance would be if it had caught up to your books.
5. Adjust the book balance. Start from your book balance. Add interest and credits; subtract fees and NSF charges. This is what your books would show if you'd known about the bank's items.
6. Confirm the two adjusted balances match. If adjusted bank equals adjusted book, you're reconciled. If they don't, a difference is still unexplained — recheck for a missed item, a math slip, or a transposed figure. A gap that's evenly divisible by 9 is very often a transposition (e.g. $270 → $720).
7. Record the adjustments in your books. The book-side items are real transactions — post the fee as an expense, the interest as income, the NSF check as a reversal. The bank-side timing items need no entry; they'll clear on their own next period. File the statement with the reconciliation.
You run a small consultancy. On August 31 your books show a cash balance of $8,450. The bank statement shows an ending balance of $9,180. They don't match — so you reconcile.
Going line by line, you find four unmatched items:
| Item | Amount | Where it is | Side to adjust |
|---|---|---|---|
| Deposit made Aug 30, not yet posted | $1,500 | Books only | Bank (+) |
| Check #204 to a supplier, not yet cashed | $2,200 | Books only | Bank (−) |
| Monthly account fee | $30 | Statement only | Book (−) |
| Interest earned | $0 | — | — |
Now apply the formula.
Adjusted bank balance = $9,180 + $1,500 (deposit in transit) − $2,200 (outstanding check) = $8,480
Adjusted book balance = $8,450 − $30 (bank fee) = $8,420
They don't match — $8,480 vs $8,420, a $60 gap. Something's still unexplained, so you look again. You find it: a client's $60 card payment posted on the statement but was never entered in your books. That's a book-side item you missed.
Adjusted book balance = $8,450 + $60 (missed card payment) − $30 (bank fee) = $8,480
Now both sides read $8,480. Reconciled. You post two entries in your books — the $30 fee as an expense and the $60 payment as income — and file the statement. The deposit in transit and the outstanding check need no entry; they'll clear next month on their own.
A bounced check is the classic reconciliation surprise, because you already spent the mental "cash" before it disappeared.
In July you invoiced a client $900, they paid by check, and you deposited it and marked the invoice paid. Your July book balance includes that $900. But the client's account was short, so the check bounced — and your August statement shows the bank reversing the $900, plus a $12 returned-item fee.
At reconciliation, both the $900 reversal and the $12 fee are on the statement but not in your books. Both are book-side adjustments:
Adjusted book balance = book balance − $900 (NSF reversal) − $12 (returned-item fee) = your true cash
The money never really arrived, so your books have to give it back. Two things follow: you record the reversal and the fee in your books, and — importantly — that $900 invoice is not paid after all. It goes back to being an outstanding invoice you need to collect, ideally with the $12 fee passed along if your terms allow. Reconciliation is what caught it; without it, you'd have kept treating $900 you don't have as money in the bank.
These sound alike and overlap, but they answer different questions.
| Bank reconciliation | Billing reconciliation | |
|---|---|---|
| What it matches | Your books ↔ your bank statement | Your invoices ↔ payments ↔ statements |
| The unit | The whole cash account | Each individual invoice |
| The question | Is my cash balance correct? | Was every invoice actually paid? |
| Catches | Fees, timing gaps, bank errors, fraud | Short payments, missing payments, misapplied payments |
In a small business you often do both, and they feed each other: billing reconciliation confirms each invoice was paid the right amount, and bank reconciliation confirms all that cash — net of fees — actually landed and your account balance is right. If you want the invoice-by-invoice side in depth, see the full guide to billing reconciliation. This page is about the account as a whole.
Most of the pain is decided before you ever open a statement — by how cleanly you record cash coming in and going out in the first place.
Bank reconciliation isn't glamorous, but it's the step that turns a guessed cash balance into a proven one. A small monthly habit catches the fee you forgot, the check that bounced, and the charge you never made — long before any of them becomes a real problem.
What is a bank reconciliation?
A bank reconciliation is the process of comparing the cash balance in your own accounting records against the balance on your bank statement, then explaining every difference between them. When both sides are adjusted and agree, the reconciliation proves your books show your true cash position. When they don't agree, you've found an error, a missing transaction, or possible fraud to investigate.
What is the bank reconciliation formula?
Adjusted bank balance = bank statement balance + deposits in transit − outstanding checks. Adjusted book balance = your book balance + interest and credits the bank added − bank fees, NSF charges, and other deductions you hadn't recorded. When the adjusted bank balance equals the adjusted book balance, the account is reconciled.
What are the steps in a bank reconciliation?
Gather your bank statement and your book balance for the same period, tick off every transaction that appears on both, list the items on only one side, adjust the bank balance for deposits in transit and outstanding checks, adjust the book balance for fees and interest, confirm the two adjusted balances match, then record the adjustments in your books.
What is the difference between a deposit in transit and an outstanding check?
A deposit in transit is money you received and recorded in your books but the bank hasn't processed yet, so it's missing from the bank statement — you add it to the bank side. An outstanding check is a check you wrote and recorded but the recipient hasn't cashed yet, so it hasn't cleared the bank — you subtract it from the bank side.
How often should you do a bank reconciliation?
At least once a month, right after your bank statement closes. Businesses with a high volume of transactions often reconcile weekly or even daily. The longer you wait, the more transactions pile up and the harder any discrepancy is to trace.
What is the difference between bank reconciliation and billing reconciliation?
Bank reconciliation matches your accounting records to your bank statement to confirm your cash balance is correct. Billing reconciliation matches your invoices to the payments you received and to your statements to confirm every bill was paid. Bank reconciliation is about the account as a whole; billing reconciliation is about individual invoices.
Clean books start with clean invoices. Create professional, uniquely numbered invoices — with due dates, terms, and itemized totals built in — using the free invoice generator. When every payment ties back to one clear invoice, each month's reconciliation becomes a quick confirmation instead of a scavenger hunt.