The single European payments area (Sepa) went live this week with the European Commission predicting potential savings of £268bn over the next six years, as well as challenges for banks.
The system, which will make all electronic payments in the Eurozone the same as making domestic payments, was launched for credit transfers.
A combination of payments-market harmonisation and e-invoicing could lead to massive savings, according to a European Commission (EC) study into costs.
"Potential benefits from Sepa in payments markets alone could exceed £91bn over the next six years, and a further £177bn if Sepa can be used as a platform for electronic invoicing," said the EC.
Although the UK does not use the euro, businesses with a presence in the Eurozone will need to change their processing systems if they want to make lower cost Sepa transactions, and UK banks will need to upgrade systems to support it.