Loan Data Migration

Loan data migration is moving existing loans and their history from an old system to a new one. It usually happens when a lender replaces its servicing tool, adopts a new platform, or moves off spreadsheets. In banking, the same project is often called a conversion.

A migration is more than copying files. For each active loan, the new system needs the current balance, the payment schedule, accrued interest, escrow or reserve balances, fees owed and the payment history that servicing and reporting depend on. Closed loans may need to move too, or be archived where staff can still find them.

Why it matters for lenders

A bad migration damages trust in the new system on day one. If balances are wrong, borrowers get wrong statements, payoff quotes are off, and the month-end close does not tie. Staff then go back to their old spreadsheets, and the new system never takes hold.

The safest approach follows a few rules:

• Reconcile before you migrate. Moving a bad balance into a new system makes it harder to find.
• Move what the loans need. Migrate what servicing, reporting and the next credit decision require. Archive the rest on purpose.
• Prove it to the cent. Each migrated balance should tie to the old system, loan by loan, and the totals should tie to the general ledger.
• Run in parallel. Process at least one full payment and month-end cycle in both systems and compare the results.
• Keep the old data. Hold a read-only copy for as long as your record-keeping rules require.

How it works in practice

A loan fund with 600 active loans is moving from an aging servicing tool to a new platform. It names a data owner, who answers for the balances, and a separate control reviewer, who challenges the results.

First, the team runs reports from the old system and fixes known problems, such as loans with missing first payment dates. Then it exports active loans and loads them into a test copy of the new system. A script compares every balance, interest accrual and next due date between the two systems. Forty loans don't match. Most differences come from how each system rounds daily interest, so the team documents a fix and reloads.

After a clean test, the fund runs one full month in both systems. Payments, interest and the month-end totals match. The fund switches its payment files to the new platform on a set date and keeps the old system read-only. The audit trail of each fix is saved for the auditors.