The pricing cap on interchange fees on Eftpos looks likely to be eased from late this year under proposals published yesterday by the Payments System Board.As foreshadowed last month by the PSB, the regulator aims to change the regulation of these wholesale, or inter-bank, fees on Eftpos payments to be consistent with those applying to the scheme debit cards.The proposal is the latest in a long line of regulatory interventions, and follow-up tinkering, by the PSB to address what it considers is a lack of competitive dynamics in aspects of the payment cards markets. The first rules, relating to credit card interchange, were introduced early this decade.The latest plan is to introduce a new cap of 12 cents on Eftpos interchange.  At present there is a floor of four cents and a cap of five cents.On scheme debit cards, issued by banks but carrying a MasterCard or Visa marque, interchange is already subject to a 12 cents cap (on the basis of a weighted average across the industry and based on historical costs).Interchange fees between banks on payment cards flow in different directions on Eftpos (where it is paid by the card-issuing bank to the merchant's bank) and scheme debit (where, as with credit cards, it is paid by the merchant's bank to the card issuing banks).This means the differential in interchange payments on alternative forms of debit payments is free to widen from 17 cents at present to 24 cents.Given that card issuing is more closely tied to customer acquisition and product innovation, and also given that MasterCard and Visa have provided plenty of financial incentives to issuers, scheme debit is steadily winning shares in the payments market at the expense of Eftpos.The latest PSB plan may not make much difference to current trends unless banks somehow negotiate a way to reverse the flow of interchange fees on Eftpos.