BUYER GUIDE · UPDATED 22 OCTOBER 2026
How to validate financial data after a system migration
Validate both completeness and financial meaning before sign-off. Compare source and target at the same cut-off, check record identity and transformations, reconcile relevant totals and retain record-level exceptions. A successful load is only evidence that the load ran.
By ShipDataFast. Published ; reviewed .
Before a mock migration
- Agree the population, extraction cut-off, currencies and accounting basis.
- Version source-to-target mappings, identifier crosswalks and expected differences.
- Define null, duplicate, rejected-row and transformation checks.
- Agree tolerances by field with finance owners; do not choose them after seeing the breaks.
- Name exception owners, reviewers and the person authorised to decide go/no-go.
Check at three levels
| Level | Example | Why it matters |
|---|---|---|
| Population | Source count, loaded count, rejected count, duplicate keys | A matching total may hide missing records |
| Financial control totals | Cash by account and currency; quantities by fund and security | A grand total may hide offsetting differences |
| Record and field | Mapped amounts, dates and code values on the agreed key | Rows can arrive with changed meaning |
Example: totals agree but records do not
Two synthetic balances of 100 and 200 become 90 and 210 after migration. The total remains 300. A record-level comparison flags both changes; an aggregate-only test passes. Where a deliberate transformation changes values, compare against the approved expected transformation and retain its rule version.
Parallel run and cutover decision
Run the same controls through representative mock loads and parallel periods. Investigate recurring timing breaks instead of silently raising tolerances. Retain unresolved issues, approved waivers and reruns. Cutover approval belongs to the authorised business owner; a tool or consultant report supplies evidence for that decision.
A scoped next step
The Migration Reconciliation Readiness Review is £1,500 + VAT for 2 days, with no access to your data needed. It reviews keys, tolerances, expected differences, ownership and sign-off. The Migration Sign-off Check is £3,750 + VAT for 5 days; agree the scope before booking.