Key takeaways
What this article covers, in order:
- What "losing your reconciliations" actually looks like
- Step 1: pick a sensible cut-over date
- Step 2: finish the old books properly
- Step 3: export what you'll need
- Step 4: carry the uncleared items across one by one
- Step 5: open debtors and creditors the same way
The secret to changing accounting software without wrecking your bank reconciliations is to cut over at the end of a fully reconciled period, take your old system's reconciliation report with you, and enter the uncleared items individually in the new system. Do that and your first reconciliation in the new software picks up exactly where the old one stopped, to the penny.
What "losing your reconciliations" actually looks like
Laura runs a three-person design studio in Glasgow. She moved software once before, years ago, and it went badly. The new system had the right opening bank balance, but two supplier payments from the last week of the old system cleared in the new one with nothing to match against. Her first reconciliation was out by £1,846.75, and it stayed that way for two months while she worked out why.
That's the classic failure. Not lost data, exactly. Lost context. The new system didn't know those payments were already "in the books" but not yet "in the bank".
Step 1: pick a sensible cut-over date
Choose the last day of a month, ideally a quarter end or your financial year end. The date matters less than one rule: the old system must be fully reconciled to that date.
Laura picks 30 Sep 2026. It's a quarter end, it's recent, and her bookkeeper can reconcile September 2026 in the old system before anything moves.
Avoid cutting over mid-month. You'll end up reconciling one statement across two systems, and that's how you get Laura's first switch all over again.
Step 2: finish the old books properly
Before you export anything:
- [ ] Reconcile every bank and credit card account to the cut-over date
- [ ] Clear or explain anything in suspense
- [ ] Bring sales invoices and supplier bills up to date
- [ ] Post any month-end journals your accountant normally does
- [ ] Agree the trial balance at the cut-over date with your accountant if possible
The old system is about to become read-only in your head, so this is your last chance to fix things cheaply.
Step 3: export what you'll need
From your old system, save these as PDF or spreadsheet files for the cut-over date:
| Report | Why you need it |
|---|---|
| Bank reconciliation report, per account | Statement balance plus the list of uncleared items |
| Trial balance | Opening balances for every account |
| Aged debtors (receivables) | Open customer invoices to carry across |
| Aged creditors (payables) | Open supplier bills to carry across |
| Chart of accounts | To map categories into the new system |
| Customer and supplier lists | Contact details for invoicing and bills |
Both big platforms keep this history for you. As of Oct 2026, Xero's help centre documents Bank Reconciliation reports for checking statement balance against the balance in Xero (Xero Central). QuickBooks Online's UK help pages describe a Reconcile Discrepancy Report and an audit log for checking what changed after a past reconciliation (QuickBooks UK help). Run them before you stop using the old system, and keep the exports somewhere you'll find them in three years.
Also keep read access to the old system for a while if you can, or at least a full export. Your accountant may want to look something up.
Step 4: carry the uncleared items across one by one
This is the step that saves the reconciliation. Here are Laura's figures at 30 Sep 2026 from her old reconciliation report:
| £ | |
|---|---|
| Balance per bank statement, 30 Sep 2026 | 18,420.60 |
| Less: supplier payment not yet cleared (printer) | (1,250.00) |
| Less: supplier payment not yet cleared (freelance copywriter) | (320.40) |
| Add: client cheque paid in 30 Sep 2026, not yet cleared | 2,100.00 |
| Balance per books, 30 Sep 2026 | 18,950.20 |
Check: £18,420.60 − £1,250.00 − £320.40 + £2,100.00 = £18,950.20.
The tempting shortcut is to enter one opening bank balance of £18,950.20 and move on. Don't. When the £1,250.00 payment clears on the October 2026 statement, there's nothing for it to match.
Instead, in the new system:
- Set the opening bank balance to the statement balance: £18,420.60.
- Enter each uncleared item as its own transaction, dated when it originally happened: the £1,250.00 and £320.40 payments, and the £2,100.00 deposit.
- Check that the bank account in the new system now shows £18,950.20, the same as the old books.
When Laura's October 2026 statement arrives, each of those three items has a partner waiting. They match, the reconciliation starts from £18,420.60, and it balances.
The other side of these entries matters too. The opening balance and the uncleared items need to land against the right accounts (the supplier balances, the debtor for the client cheque, and your opening balances), so the trial balance in the new system agrees with the old one. This is fiddly the first time, and it's exactly where your accountant is worth a short call.
Step 5: open debtors and creditors the same way
Do the same for customers and suppliers: enter each open invoice and bill individually, with its original date and number, rather than one lump per customer. That way:
- Payments received in October 2026 match the actual invoice the customer is paying.
- Your aged debtors report is right from day one.
- Chasing doesn't stall because "Opening balance" isn't an invoice anyone recognises.
Step 6: run both systems for one month (lightly)
You don't need to keep full books in both. But for the first month, it's worth running your first reconciliation in the new system and comparing the closing balance to what the old system would have shown. If the balance at 31 Oct 2026 agrees with the bank statement, and the trial balance at 30 Sep 2026 agrees with the old one, you're done.
Common switching mistakes
- Cutting over mid-month. Split statements are miserable to reconcile.
- One lump opening balance for the bank. Uncleared items have nothing to match against.
- Lump balances per customer. Payments can't be matched to real invoices.
- Skipping the old reconciliation. You carry old errors into new software and blame the new software.
- Throwing away the old reports. Your evidence of what was reconciled lives there.
How HelloBooks helps
We move your books for you. If you're coming from QuickBooks, our done-for-you QuickBooks migration service starts from $199 (USD); in the UK it works by file import, using exports from your old system. If you're coming from Xero, we'll move your books for you as well. More on both on our Xero alternative and QuickBooks alternative pages.
Once you're in, connect your bank through Open Banking (most UK banks and cards) or import a CSV statement. The reconcile screen lines your statement up against your ledger with an AI match suggestion on each line, including those carried-over uncleared items, and shows a confidence score and why it picked each match. You only work through the exceptions. Your first reconciliation report (opening balance, cleared items, outstanding items, closing balance) exports as PDF or CSV, so you can file it right next to the last one from your old system. You can also invite your accountant or bookkeeper into the same books to check the opening balances.
FAQs
What's the best time of year to switch?
Your financial year end is cleanest, because the new system starts with a fresh year. A quarter end or month end works too, as long as the old system is reconciled to that date.
Do I need to bring all my old transactions across?
Usually not. Opening balances plus uncleared and open items are enough for day-to-day work. Keep the old system's reports for the history.
What if my old reconciliation was already wrong?
Fix it before you switch, or at least document the difference. Carrying an unexplained gap into new software just moves the problem.
Can I switch partway through my financial year?
Yes. You'll need opening balances at the cut-over date rather than at year end, and your accountant will want the year's figures from both systems.
How long does a switch take?
For a small business with tidy books, the cut-over work itself is often a few hours plus a check by your accountant. Messy books take longer, which is another reason to finish the old reconciliation first.
Close the old books cleanly, carry the loose ends across one by one, and your first new reconciliation will feel like any other month.
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