my reconciliation won't balance, the statement doesn't tie out

A reconciliation that won't balance is almost always one of a short list of causes, and the difference itself usually tells you which.

Work through these in order:

• Is the closing balance right? The single most common cause: a typo in the closing figure, or a statement period that doesn't match the dates you're reconciling
• Does the difference equal one transaction? Then that transaction is either missing, entered twice, or on the wrong side. Search the amount
• Is the difference divisible by 9? That's the classic sign of transposed digits: 45.90 entered as 49.50
• Are there duplicates? Especially where a bank feed and an uploaded statement both brought in the same period
• Is anything dated outside the period but ticked as cleared, or cleared inside the period but dated outside it

Where the opening balance comes in

If the difference has been carried since you started, the problem isn't this month: it's the opening balance or an unreconciled earlier period. Fixing this month's entries won't close a gap that was inherited, so it's worth going back to where the two last agreed.

Talisk flags where a statement doesn't chain onto the previous one, which catches the "missing month" version of this before you go hunting line by line.