Core banking migration for a regional commercial bank
A full core banking platform migration — 1.2 million accounts, 14 integrated systems, zero unplanned downtime at cutover.
- 1.2M
- Accounts migrated
- 14
- Systems integrated
- 0
- Unplanned downtime
The challenge
The bank was running a heavily customized legacy core approaching end of vendor support. Fourteen downstream systems — channels, payments, regulatory reporting — depended on interfaces nobody fully documented. Two previous migration attempts had been abandoned at the planning stage.
What we did
NotionwaveTech took ownership of the interface landscape first: every integration was documented, rebuilt against the new core, and regression-tested in an isolated environment. Data migration was rehearsed through five full dress runs, each reconciled to the ledger. Cutover was executed over a single weekend with a staffed command center and rehearsed rollback at every gate.
The result
The bank opened Monday morning on the new platform with every balance reconciled and every channel operational. Post-migration defect volumes fell below the industry benchmark within three weeks, and the hypercare period closed two weeks early.