Your accounting file says $34,207.15. Your bank says $31,880.42. The gap is $2,326.73 and it is not obvious where it came from.
Before assuming something is broken: a difference between the two is normal and expected. The two numbers are measuring slightly different things. What matters is whether you can explain the difference — an explained gap is fine, an unexplained one is not.
1. Outstanding transactions
The most common answer by a wide margin. You wrote a cheque or scheduled a payment; the books recorded it immediately; the bank has not seen it yet.
These appear in your reconciliation screen as uncleared items. If your gap equals the total of uncleared transactions, nothing is wrong at all. That is the system working as designed.
2. The bank feed is behind
Feeds lag, and they sometimes stall silently for days without any error state. Check the last imported transaction date against today. If the feed stopped on the 9th and it is the 14th, five days of activity is simply missing from the file.
3. Duplicates
The reverse problem, and more insidious. A transaction gets entered manually and then imported by the feed, so it exists twice. Or a feed reconnection re-imports a period already loaded.
Duplicates make your book balance lower than the bank for duplicated expenses. Sort by amount and scan for identical pairs close together in date — they usually cluster around whenever the feed was reconnected.
4. A transaction was edited after being reconciled
This is the one that quietly destroys trust in a file. A previously reconciled transaction gets its amount or date changed months later. The old reconciliation still shows as complete, but its closing balance no longer holds.
Most software will warn you when it happens. Most people click through the warning. If your file has been reconciling cleanly for a year and suddenly does not, this is the first thing to check.
5. The opening balance was wrong
If the discrepancy has existed since the file was created and never changed, the starting balance was probably entered incorrectly at setup. Everything since has been accurate; the whole ledger simply sits on a wrong foundation.
Diagnosis is easy: if the gap is a constant amount over many months rather than a moving one, look at the beginning rather than the recent activity.
6. Someone forced it
The genuinely bad one. A previous reconciliation would not balance, so an adjusting entry was posted to make the difference disappear.
Look for a journal entry with a description like "reconciliation adjustment," an odd non-round amount, and no supporting documentation. The underlying error was never found — it was papered over, and it is still in the file, now disguised as a legitimate entry.
How to actually find it
Work backwards, not forwards. Find the most recent month where the reconciliation was genuinely clean, then move forward one month at a time until it breaks. That isolates the problem to a single period instead of a year.
Within that month, the difference amount itself is a clue. A gap that is exactly divisible by nine is often a transposition — 5,481 entered as 5,148. A gap equal to exactly twice a transaction you recognise is a duplicate. A round number is often a manual entry someone made deliberately.
If the file has several months of this stacked up, it is usually faster to have someone work it period by period than to keep hunting. That is the bulk of what a cleanup actually is — and the reason we never force a reconciliation to zero is that every plug entry becomes someone's problem later.
Behind on Your Books?
We handle your bookkeeping end-to-end — categorization, reconciliation, month-end close, and clean financial statements, so your books stay current and CPA-ready.