Payment institutions and electronic money institutions are governed by the Law of 10 November 2009 on payment services ("the PSL"). The PSL results from the transposition of Directives 2007/64/EC of 13 November 2007 on payments services in the internal market and 2009/110/EC of 16 September 2009 on the taking up, pursuit and prudential supervision of the business of electronic money institutions.

Payment services are defined in Article 1(38) of the PSL as "any business activity performed on a professional basis listed in the Annex". Payment services are listed exhaustively in the Annex to the PSL.

Electronic money is defined in Article 1(29) of the PSL. It is "a monetary value represented by a claim on the issuer, which is (i) electronically, including magnetically, stored, and (ii) issued on receipt of funds for the purpose of making payment transactions, and (iii) accepted by a natural or legal person other than the electronic money issuer".