Xero Migration Risks: 10 Critical Checks Every Business Should Make After Data Migration
When migrating from traditional accounting software to Xero, the process is far more than a simple data import. A successful Xero migration requires careful planning, expert reconciliation, and an in-depth review of your financial records — both before and after the switch. Check below for more xero migration risks.
As a trusted Xero Gold Partner, we’ve worked with countless businesses and have seen what can go wrong when migrations are rushed or handled by inexperienced providers. From data discrepancies to auditor red flags, here are 10 essential checks to carry out post-migration to avoid costly mistakes and ensure data integrity.
1. Reconcile Trial Balances (Cut-Off and Historical Periods)
Your trial balance is the cornerstone of financial accuracy. After migration, you must compare the trial balance in your old system with the one in Xero for:
- The migration cut-off date
- The prior year-end
- Monthly snapshots (if your reports are period-based)
Many large ERP systems, such as Sage 200 or Exchequer, use accounting periods instead of transaction dates. If your migration specialist hasn’t carefully mapped these using posted dates, your monthly comparisons will be unreliable.
Watch out for:
- Unexplained dummy nominal codes
- Suspicious manual adjustments to sensitive accounts (like VAT or retained earnings)
Auditors and HMRC take these anomalies seriously — especially if they appear to mask missing transactions or reconciliation issues.
2. Compare Aged Debtors and Creditors (Including Prior Year)
Another critical reconciliation point is your aged debtors and creditors reports. These should match precisely between systems at the migration cut-off and ideally at the prior year-end too.
Why it matters:
- Many ERP systems store customer and supplier records in separate modules
- During migration, contact records can be merged, split, or misaligned
- We’ve seen providers accidentally merge customer accounts, leading to:
- Incorrect customer statements
- Misallocated payments
- Confused staff and angry clients
You must reconcile balances per individual contact, not just at summary level.
3. Validate Contact Data Integrity
Your contact database is the foundation for invoicing, payment reminders, VAT settings, and customer communication. After migration, export your full contact list from Xero and check for:
- Duplicated contacts
- Missing email addresses, VAT codes, or default nominal codes
- Contacts with no account numbers
- Special characters or corrupted data in names and addresses
We’ve seen cases where providers import contact names with unreadable symbols — this breaks your templates, emails, and causes invoicing errors.
A proper data migration specialist will map and test all contact fields to avoid these Xero migration risks.
4. Review Manual Journals for Red Flags
Post-migration journal entries can reveal whether your provider has masked underlying issues.
Scrutinise any journals posted to:
- Retained Earnings
- VAT Liability
- Suspense
- Dummy Nominal Codes
- Exchange Gains or Losses
These entries might indicate:
- Missed or duplicated transactions
- Mismatches in supplier/customer allocations
- Forced trial balance adjustments to make numbers “look right”
Manual journals should be minimal, transparent, and fully explained — not a patchwork hiding flaws in the migration.
5. Check for Signs of Manual Processing
High-quality Xero data migrations should be automated using structured import tools, not manual data entry. Manual intervention increases the risk of:
- Human error in key figures
- Wrong payment allocations
- Inconsistent treatment of overpayments, refunds, and credit notes
Every system handles allocations differently. If your migration didn’t accurately replicate the logic from your old system, your sales and purchase ledgers will not reconcile properly.
We’ve seen providers try to manually “reconcile” banks or match payments, resulting in serious misallocations and long-term reporting issues.
6. Validate Invoice Due Dates
A simple but costly mistake: incorrect due dates on sales and purchase invoices.
Legacy systems often don’t offer clear reports with individual transaction due dates, so some providers default to the invoice date. This disrupts your:
- Credit control routines
- Supplier payment schedules
- Expected cash flow
Run a spot check on several invoices and credit notes. The due dates should reflect the correct terms agreed with each contact, not assumptions or defaults.
7. Compare VAT Returns (Old vs Xero)
VAT is one of the most sensitive areas in any migration. Run a VAT return report in both your old system and Xero, and compare:
- All 9 VAT boxes
- Any differences caused by late reconciliations
- VAT codes applied to transactions
We’ve uncovered cases where providers migrate transactions with “No VAT” instead of correct codes like Zero Rated, Exempt, or EC Sales. These errors can:
- Trigger audits
- Result in over- or underpaid VAT
- Create compliance issues with HMRC
If you’re preparing your first VAT return in Xero, this is a critical review step.
8. Daily Bank Reconciliation Comparison
Your bank balance is one of the easiest and most accurate indicators of migration success — if it’s done correctly.
We recommend a daily reconciliation comparison between your old system and Xero for the current financial year. This helps uncover:
- Misdated transactions
- Missing receipts or payments
- Incorrect opening balances
Bank discrepancies, even minor ones, will snowball over time and affect reconciliations, cash flow projections, and audit trails.
9. Verify Sales Invoices and Credit Notes Numbers
Your invoice and credit note numbers are vital for continuity. After migration:
- Check that invoice numbers match the original system
- Ensure Xero hasn’t applied automatic numbering
- Verify that credit notes are linked to the correct sales invoices
We’ve seen failed migrations where providers import invoices using Xero’s default numbers — confusing customers and making it hard to track payment history.
10. Audit Conversion Balances and Adjustments
Your conversion balances (or opening balances) should be consistent with the data at your migration cut-off date. They must not be back-engineered just to force a trial balance match.
Key steps:
- Request full audit logs of adjustments made after migration
- Ensure the conversion balance entries match original reports
- Question any unexplained rounding differences, suspense entries, or dummy accounts
Inaccurate opening balances can result in:
- Failed audits
- Misstated financial reports
- Penalties from HMRC
A professional Xero expert will provide a detailed reconciliation pack, outlining every adjustment and matching point-by-point with your original system.
🔍 Final Thoughts: Don’t Rely on Assumptions. Validate Everything.
Even a clean-looking migration can hide serious issues beneath the surface. Whether you’re switching from Sage 200, Access , Exchequer, or another legacy ERP, your provider must demonstrate:
- Full reconciliations
- Contact accuracy
- Trial balance integrity
- VAT correctness
- Bank alignment
At MigrateMyAccounts.co.uk, we don’t just move your data — we preserve its accuracy and structure it to work with Xero’s ecosystem. That’s what makes us a trusted Xero Gold Partner.
✅ Considering a switch to Xero or worried about a past migration?
Let’s review it together. We specialise in:
- Xero migration rescue and reconciliation
- Historical data clean-up
- Custom reporting configuration
- Xero training for finance teams
