National Australia Bank on Thursday said it could re-register its subsidiary Clydesdale Bank in England if Scotland votes for independence next week.
The Australian bank confirmed its contingency planning in the event of a "Yes" vote included "seeking registration as an English company".
"Re-registration would address some of the uncertainties and risks surrounding terms of separation if Scotland were to become an independent country," NAB said in a statement.
Royal Bank of Scotland said Thursday it would move its offices out of the country in the event of a "Yes" vote, while Lloyds said it would also reconsider its position.
NAB group chief executive Andrew Thorburn added that registering Clydesdale, one of Scotland's largest banks, in England "would provide greater clarity going forward".
"This contingency plan gives our Clydesdale and Yorkshire Bank customers increased certainty about the ongoing success and stability of the bank," Thorburn said.
NAB added that the re-registration in England would be subject to regulatory approvals.