How to investigate duplicate transactions after statement conversion

Same amount does not automatically mean a duplicate

Recurring debit orders, service fees, transfers and card purchases can share an amount and a similar description. A duplicate should only be removed after checking its date, reference, direction and place in the bank's source order. Two genuine transactions can happen on the same day.

Start by grouping candidate rows, then compare each group back to the original PDF. A duplicate created during extraction often appears as an identical row beside or near its source row, while a genuine repeat usually has a distinct reference, merchant detail or source position.

Check for page breaks and wrapped descriptions

Statement tables can continue across a page break, with the final row on one page and its description continuing on the next. A review workflow should confirm that the description was attached once to the correct date and amount rather than becoming a separate transaction.

Look carefully at rows near headers, footers and page transitions. A repeated column heading is not a transaction, and a brought-forward balance should not be imported as one. Source-order review makes these layout patterns easier to identify.

Review checklist

• Review every page transition
• Check wrapped merchant and reference lines
• Exclude headings, totals and carried balances

Recognise reversals and refunds

A reversal or refund may have the same amount as the original charge, but it should normally carry the opposite sign and a later date. Removing it as a duplicate would overstate the expense. Compare the signs and description wording before deciding whether a pair should remain.

Some banks label these entries as reversal, refund, reversed card transaction or returned payment. Others provide only a reference. If the relationship is not clear on the statement, retain both records and investigate in the banking portal rather than guessing from an exported file.

Prevent duplicate imports after export

A correct spreadsheet can still be imported twice. Before each accounting import, record the exact source account, statement period, export date and the first and last transaction. Import a small, recoverable period first when the receiving system's duplicate controls are unfamiliar.

Do not rely solely on an OFX application's duplicate detection. Different products compare different combinations of dates, amounts and identifiers. Preserve a simple import register so an overlapping period is visible before it creates a reconciliation problem.

Review checklist

• Record source account and statement period
• Keep an import register
• Test new accounting software with a small range first