CPA (Cost Per Action) Refers to affiliate program that operate in a pay per lead or pay per sale structure. The affiliate is being paid per sale or lead that his traffic generates. CPA (Cost Per Action) This is the rate/fee that is set for every action that is taken by on visitor which is promoted by an affiliate. This usually refers to, by not limited to, Pay Per Lead and Pay Per Sale transactions. CPA, as Cost Per Action usually corresponds to Pay Per Lead while CPA, as Cost Per Acquisition usually corresponds to Pay Per Sale. Pay Per Lead (PPL) Affiliate network or program which pays commission per leads. Pay Per Sale (PPS) Affiliate network or program which pays commission per sale. Feel free to post your comment. Thanks and have a great day!