OFX vs CSV for Bank Reconciliation: Which Should You Use?

TL;DR: Use OFX for bank reconciliation when your software accepts it. OFX carries a unique transaction ID (FITID) on every line, so re-importing an overlapping period will not create duplicates, and it declares the account and closing balance so the software can verify nothing was dropped. CSV has neither. CSV is the better choice when you need to inspect, categorize, or reshape the data by hand, or when the destination system only takes a spreadsheet.

What is the difference between OFX and CSV for reconciliation?

The difference that actually matters at reconciliation time is not readability. It is that OFX is self describing and CSV is not. An OFX file states which account the transactions belong to, which date range they cover, what the closing balance was, and gives every transaction a stable ID. A CSV is just rows of text whose meaning depends entirely on whoever wrote the column headers.

That distinction decides how much manual checking you have to do:

Why does duplicate protection matter so much?

Because the most common way a reconciliation breaks is not a missing transaction. It is a doubled one. You import a statement, notice a few days at the end were still pending, pull a fresh file the following week, import that too, and now the overlapping days exist twice in the register. The balance is off by exactly the sum of the overlap, and finding that by eye in a few hundred lines is genuinely tedious.

OFX solves this structurally. Every transaction carries a FITID assigned by the institution. When you import a file containing transactions the software has already seen, it matches on that ID and skips them. You can re-import the same period repeatedly and the register stays correct. With CSV there is no identifier, so the software either creates duplicates or falls back to fuzzy matching on date and amount, which quietly merges two genuinely separate identical charges. Both failure modes cost you time.

When should I use CSV instead?

CSV wins whenever a human needs to touch the data before it lands anywhere. Specifically:

• Categorizing before import. If you assign categories or classes in bulk, doing it in a spreadsheet with fill down is far faster than clicking through a register.
• The destination only takes CSV. Many modern accounting tools and custom ledgers accept CSV import and nothing else.
• Analysis rather than posting. For pivots, spend by category, or a schedule for a tax return, you want a sheet, not an account file.
• Cleaning messy descriptions. Find and replace across a description column beats editing entries one at a time.
• Handing data to someone else. An accountant who has not asked for a specific format will almost always prefer a spreadsheet.

The practical middle ground a lot of bookkeepers use: reconcile from OFX so the register stays clean and duplicate free, and separately export or convert to CSV for the analysis and categorization work. The two formats are not really competing. They serve different steps.

Which format is more accurate?

Neither format is more accurate in itself. Both can represent the same transactions correctly. What differs is how many chances there are for something to go wrong between the bank and your books. OFX has fewer, because the structure is fixed and the software validates the account and balance for you. CSV has more, because column order, date format, sign convention, and header naming all vary by source and all have to be interpreted correctly.

The most frequent CSV reconciliation errors come from that variability. A file with separate debit and credit columns imported as if it had one signed column produces a total that is wrong by twice the credits. A date column read as US format when it was written in another produces transactions in the wrong month. Neither error announces itself. You find out when the balance does not tie.

Does OFX work with every accounting program?

No, and this is usually what settles the decision. Quicken and MS Money import OFX and QFX natively. GnuCash and Moneydance import OFX. QuickBooks wants QBO, which is Intuit's own flavor of the same underlying format. A lot of newer cloud accounting tools skipped OFX support entirely and accept only CSV, or a direct bank feed.

So the real sequence is: check what your software takes, and prefer OFX if it is on the list. If your program only reads CSV, use CSV and add your own duplicate discipline, which in practice means importing strictly non overlapping date ranges and reconciling every period before moving to the next.

What about the bank feed instead of a file?

A direct bank feed is usually better than either file format for current transactions, since it handles duplicates and account matching automatically. Files matter for everything a feed cannot reach. Most banks only expose 90 days or so of downloadable history, feeds break during bank migrations, and prior year cleanup work routinely needs data far older than any feed offers. That is where converting statements to a proper account file earns its keep.

Getting the format you actually need

If your bank hands you only a PDF, you can produce either format from it. Convert the statement to an account file with the bank statement to OFX converter when you want duplicate safe importing, or straight to a sheet with the PDF to CSV converter when you want to work with the data by hand. If you already have an OFX and need it in a spreadsheet, the OFX to CSV converter handles that direction, and the CSV to OFX converter goes back the other way when a program insists on an account file.

Reconciliation also tends to surface expenses with no matching paperwork, which is a separate problem from format. Teams that struggle with that usually fix it upstream by having receipts captured and categorized as they come in, so the documentation already exists by the time anyone opens the statement.

The short decision rule

If the transactions are going into a register you will reconcile against a statement balance, use OFX. If the data is going into a spreadsheet, a report, or a system that only speaks CSV, use CSV. If you are doing both, which most bookkeepers are, use OFX for the posting and CSV for the analysis, and keep them as separate steps rather than trying to make one file serve both jobs.