First, be sure switching is the answer
Write down the three things your current system cannot do. If they are reporting gaps, a missing integration or poor bank feeds, check whether an add-on or a different plan solves it. If the real issue is process — nobody reconciling, no credit control routine — new software will not fix that. Good reasons to move include unsupported legacy desktop software, no Making Tax Digital compliance, pricing that no longer stacks up, multi- currency or inventory needs, or your accountant working in a different platform.
Talk to your accountant before you choose
Your accountant or bookkeeper works in these systems daily and often has partner pricing. More importantly, they will be the ones producing your year-end from the migrated data, so they should agree the cut-over date and the opening balances approach.
Choose the timing carefully
The safest moment to move is the start of a new financial year, with the previous year closed off. The second-best is the start of a VAT quarter. Never migrate mid-quarter with a VAT return due in a fortnight, and avoid your busiest trading period and payroll year-end.
Decide how much history to bring across
You rarely need every transaction. Most businesses migrate opening trial balance, outstanding sales and purchase invoices, unreconciled bank items, customer and supplier records, the chart of accounts and product or service lists. Older detail can stay in a read-only archive or exported files. HMRC expects records to be kept for at least six years, so keep an accessible export of the old system even after you stop paying for it.
Check VAT and Making Tax Digital
- The new package must be MTD-compatible and reconnected to HMRC before your first return
- Re-authorise the HMRC connection — it does not transfer with your data
- Carry over the correct VAT scheme: standard, cash accounting or flat rate
- Watch for partially reclaimed VAT and any VAT on unpaid invoices at cut-over
- Keep the digital links unbroken if you use spreadsheets anywhere in the chain
Re-check every integration
List everything currently plugged into your accounts: bank feeds, payroll, card and payment providers, e-commerce or EPOS, expenses apps, stock systems, CRM and any reporting tool. Confirm each one connects to the new platform before you commit, and budget time to reconnect bank feeds, which usually require fresh authorisation and can take a few days.
Run both systems briefly, then reconcile
Keep the old system read-only for a month or two after cut-over. Immediately after migration, reconcile the numbers that matter: trial balance, bank balances, aged debtors, aged creditors, VAT control account and, if relevant, stock valuation. If those six agree, the migration was clean.
Train the team and rewrite the routine
Book the training the software provider includes, and rewrite your monthly routine as a simple checklist for the new system — raising invoices, chasing payment, reconciling the bank, running reports. Set user permissions properly at the same time so not everyone is an administrator.
Migration checklist
- Cut-over date agreed with your accountant
- Full export and backup of the old system, stored safely
- Chart of accounts mapped and tidied
- Opening balances agreed and entered
- Open invoices, credit notes and unreconciled items brought over
- VAT scheme set and HMRC reconnected
- Bank feeds and integrations live and tested
- Six key balances reconciled against the old system
- Team trained, permissions set, old system made read-only
Next step
If you would like help with the migration itself, you can find accountants, tax specialists and financial advisors in the accountancy category, or read how to choose a CRM system for a similar selection framework.