Nordea is uprooting its headquarters from Sweden to Finland in a move that could save up to €1bn in costs.
The biggest bank in Scandinavia announced its intentions this week, news that comes as a major blow to Stockholm's hopes of establishing itself as one of Europe's financial capitals.
Sweden's government, through its Swedish Financial Supervisory Authority (SFSA), has tightened regulations in the sector ever since the market crash in 2008.
In Finland, Nordea will be supervised by the European Central Bank - currently not an option in Sweden and understood to be another of the main factors behind the institution's decision.
"They want the security that the banking union provides, and that leaves Finland as the alternative that can provide that," Exane BNP Paribas analyst Andreas Hakansson told Reuters.
In a statement, Nordea confirmed the move but reassured investors and customers that its operations on the continent will be unchanged and that it will affect only a small number of employees.
The re-domiciliation will be completed as a cross-border merger between Nordea AB and a newly-established Finnish subsidiary.