Why Banks and Books Never Agree
The starting point for understanding bank reconciliation is accepting that the bank balance and the book balance will almost never be equal at month-end — and that this is completely normal. The difference is not necessarily an error. It is usually caused by timing: transactions that have been recorded in one place but not yet in the other.
The goal of the bank reconciliation is to identify every reconciling item, explain why each difference exists, and arrive at the same adjusted (true) cash balance from both the bank side and the book side. If both sides do not reach the same adjusted balance, there is an error somewhere that must be found and corrected.
The Two-Column Format: Bank Side vs Book Side
A bank reconciliation has two independent sections that are solved separately but must produce the same final number.
+ Deposits in transit
− Outstanding checks
± Bank errors
= Adjusted bank balance
+ Bank credits not yet recorded (e.g. note collected by bank, interest earned)
− Bank debits not yet recorded (e.g. NSF checks, bank service charges)
± Book errors
= Adjusted book balance
Every Reconciling Item Explained
Bank-Side Adjustments
Deposits in transit are deposits the company has recorded in its books and sent to the bank, but that have not yet been processed by the bank (typically deposited near month-end). They appear in the company's cash account but not on the bank statement — so they are added to the bank balance.
Outstanding checks are checks the company has issued and recorded as payments but that have not yet cleared the bank. They reduce the company's book balance but have not reduced the bank balance yet — so they are deducted from the bank balance.
Bank errors are rare but do occur. If the bank incorrectly posted a transaction to the wrong account, it must be corrected on the bank side of the reconciliation. The company should also contact the bank to request correction.
Book-Side Adjustments
Interest earned on the bank account is credited by the bank and appears on the statement, but the company may not have recorded it yet. Add to book balance; record an entry debiting Cash and crediting Interest Revenue.
NSF (non-sufficient funds) checks occur when a customer's check bounces. The bank reverses the deposit, reducing the company's bank balance. The company must reverse its original cash receipt entry — deduct from book balance.
Bank service charges appear on the statement but are not recorded in the books until the reconciliation. Deduct from book balance; debit Bank Charges Expense and credit Cash.
Notes collected by the bank occur when the company has authorised the bank to collect a note receivable on its behalf. The proceeds appear on the bank statement but may not be in the books. Add to book balance; debit Cash and credit Notes Receivable (and Interest Revenue for any interest collected).
Book errors are mistakes in the company's own records — a transposition error, a check recorded for the wrong amount, or a deposit posted to the wrong account. Correct on the book side.
Full Worked Example Step by Step
Greenfield Trading reconciles its bank account for the month ended 31 May 2026. The bank statement shows a closing balance of $14,820. The general ledger cash account shows a balance of $12,490. The following information is available:
- A deposit of $3,200 was mailed to the bank on 31 May but does not appear on the statement (deposit in transit)
- Checks #412 ($600), #418 ($950), and #421 ($380) have not cleared the bank (outstanding checks: $1,930)
- The bank collected a $2,000 note receivable plus $80 interest on Greenfield's behalf; neither has been recorded in the books
- The bank charged a $30 monthly service fee, not yet recorded in the books
- An NSF check for $440 was returned; the original receipt had been recorded as cash
- Check #409 was recorded in the books as $520 but actually cleared the bank for $250 — the company overstated the payment by $270 (book error: book balance is understated by $270)
| Bank Side | Amount | Book Side | Amount |
|---|---|---|---|
| Balance per bank statement | 14,820 | Balance per books | 12,490 |
| Add: Deposit in transit | 3,200 | Add: Note + interest collected | 2,080 |
| Less: Outstanding checks | (1,930) | Less: NSF check returned | (440) |
| Less: Bank service charge | (30) | ||
| Add: Book error (check #409) | 270 | ||
| Adjusted bank balance | 16,090 | Adjusted book balance | 14,370 |
The Journal Entries You Must Record
This is where many students lose marks. Only book-side adjustments require journal entries — those are the items that are correct on the bank statement but not yet in the company's own records. Bank-side adjustments (deposits in transit, outstanding checks) are already in the company's books; they simply have not hit the bank yet, so no entry is needed for them.
| Item | Debit | Credit |
|---|---|---|
| Note + interest collected by bank | Cash $2,080 | Notes Receivable $2,000 / Interest Revenue $80 |
| Bank service charge | Bank Charges Expense $30 | Cash $30 |
| NSF check returned | Accounts Receivable $440 | Cash $440 |
| Book error — check #409 overstated | Cash $270 | Accounts Payable $270 |
After posting these journal entries, the general ledger Cash account balance will equal the adjusted book balance on the reconciliation — which should also equal the adjusted bank balance. That verified number is the true cash balance that appears on the balance sheet.
Bank Reconciliation as an Internal Control
Bank reconciliations serve a purpose far beyond accounting accuracy. They are a fundamental internal control over cash — the asset most susceptible to theft and misappropriation. Performing the reconciliation monthly catches errors quickly, detects unauthorised transactions, and creates accountability for the cash balance.
For internal control purposes, the reconciliation should be performed by someone who does not handle cash receipts or issue checks. Segregation of duties between the person who authorises payments, the person who records them, and the person who reconciles the bank statement dramatically reduces the opportunity for undetected fraud. Learn more about internal controls in accounting.
Common Exam Mistakes to Avoid
- Recording journal entries for bank-side items. Deposits in transit and outstanding checks require no entry — they are already in the books.
- Adding when you should subtract (or vice versa). Use the logic: does this item increase or decrease the relevant balance? Outstanding checks reduce what the bank owes you — subtract. Deposits in transit increase what the bank will reflect — add.
- Forgetting the book error adjustment. Book errors affect the book side, not the bank side. Determine whether the error overstated or understated the book balance and adjust accordingly.
- Stopping before recording journal entries. A complete bank reconciliation answer includes the reconciliation statement AND all required journal entries. Stopping at the reconciliation costs you half the marks in most exam questions.
Practice Bank Reconciliation Questions
PrepQBank generates fresh bank reconciliation scenarios at every difficulty level — from basic two-item reconciliations to complex multi-item problems with book errors and NSF checks.
Practice bank reconciliation →