When the balance won't match: common causes

Start with the cheap checks. Most differences come from a short list of causes. Work through it in order, and change nothing until you know why.

One reference lists timing differences, missing or duplicate transactions, fees, interest or errors. It adds that they typically need to be investigated before any adjustment is made¹.

What to gather first

• The statement and its ending balance.
• The list of lines still unmatched on both sides.
• The size of the difference. A number helps: does it equal one line, or twice one line?

Causes to check, in order

Wrong dates. Is the statement date right? Are you comparing the same period? A line dated one day either side of the cut-off is a classic. It's timing, not an error. Timing differences are one of the three reasons the Wikipedia article gives¹.

Unpresented payments. A cheque you've issued may not have reached the bank yet. The reference calls these issued cheques that have still not been presented at the bank for payment¹. They're not an error. They just sit on your side until they clear.

Fees and interest. Business Central's manual notes that sometimes a bank statement contains amounts for interest or fees charged, and these have no related entry in your books until you record them².

A line entered differently. The amount or the customer name may have been entered differently in the bank transaction and in your own posting, so they don't pair up². Look at the pair side by side.

Duplicates and missing lines. A payment recorded twice, or not at all. If the difference equals exactly one payment, look there first. Also look at a file import that overlapped the previous one. The page on file imports covers that risk.

Entries posted around the bank account. The same manual warns that direct postings to the underlying account that aren't balanced often lead to accumulated differences for future reconciliations². Your product may have a similar trap.

Foreign currency. Currency conversion can result in small differences². See your product's help for how it treats exchange rates.

The previous month. If last month's reconciliation was wrong, this one carries the error. Business Central offers an Undo action for a posted reconciliation that has a mistake². Check your own product before you reopen anything.

What not to do

Don't enter a plug figure to make the totals agree. It hides the cause, and the difference comes back next month.

If the bank itself made the mistake, tell the bank. A statement isn't normally changed after it's issued, and the correction would normally appear on a future statement³.

When to stop

If you've been through the list and still have a gap, stop and ask your accountant or bookkeeper. They can read your ledger in a way that a checklist can't.