New online-only banks are often not as careful with customer privacy as longer established banks with online operations, the Dutch consumers’ association Consumentenbond said on Tuesday.

The association looked at 13 online banks and found four did not have their privacy policy up to scratch. One, Revolut, merited a score of ‘insufficient’ for passing on customer details such as email addresses and phone numbers to Facebook in return for advertising space.

In addition Revolut’s app shares information with marketing agencies without asking permission, the Consumentenbond said.

The apps operated by Bunq and N26 also communicated directly with third parties which monitored customer behaviour. Bunq told the association that the only reason for this is to improve the functioning of the website.

The four problem banks also attach advertising cookies to their users, and Revolut and Bunq fail to ask permission to do this. N26 and Openbank do ask, but not in the correct way, the Consumentenbond said.

‘The way new banks are breaking privacy legislation is unacceptable,’ Consumentenbond director Sandra Molenaar said. ‘We will keep checking and if these banks don’t solve the problems, we will report them to the privacy watchdog Autoriteit Persoonsgegevens.’