Why bank statement balances do not reconcile
A mismatch is a clue, not a reason to edit numbers until they fit. Find the first point where the source and export part ways.
Start with the right opening balance
A reconciliation begins with the opening balance for the exact account and period in the statement. If the spreadsheet starts one day late, includes a row from the previous period, or combines two accounts, every later balance can look wrong even when individual transactions are correct. Confirm the account identifier, currency, statement dates and printed opening amount before checking rows.
Some banks print an available balance, current balance and ledger balance in different places. They do not necessarily include the same pending activity. Use the balance specifically tied to the transaction history you are converting.
Find the first row that breaks the sequence
For a simple posted-transaction ledger, the expected calculation is previous balance plus the signed transaction amount equals the next balance. Work down the rows in source order and stop at the first mismatch. That is more efficient than comparing only the opening and closing totals.
When the first difference exactly matches one transaction, suspect a missing or duplicated row. When it is twice an amount, the transaction may have the wrong sign. A small difference can come from a fee or a rounding or currency-conversion line that was overlooked.
Check debits, credits and reversals
Statement designs use different conventions: separate money-out and money-in columns, signed amounts, parentheses, or labels such as DR and CR. A refund or reversal can resemble the original charge in its description while moving the balance in the opposite direction. Compare the column and the resulting balance, not just the wording.
Credit-card statements need extra care. A payment to the card reduces the amount owed, but the direction can appear different from a checking-account deposit. Do not impose checking-account rules on a card ledger without checking its headings.
Separate posted activity from information lines
Balance carried forward, page subtotals, opening balance and closing balance are usually summary lines, not additional transactions. Including one as a transaction duplicates value. Conversely, a real fee printed below a page subtotal can be easy to miss. The source layout, transaction date and description together help distinguish the two.
Pending authorizations may appear in an app but not on a monthly PDF statement, or they may post under a different date and amount. Reconcile against one source and one point in time. A current online balance should not be expected to match a statement that ended weeks earlier.
Review the extraction, then preserve the correction
OCR can confuse 8 with 3, lose a minus sign or merge adjacent rows. In the converter, inspect low-confidence entries and the first or last rows on each page. Correct the working table using the original statement. If a running balance is not printed, leave it empty instead of deriving a value and presenting it as a source figure.
After the totals reconcile, save the original statement alongside your CSV or Excel .xlsx file. If you changed a date, description or amount, note what was corrected and why. That record is especially important when someone else will rely on the export.