Commonwealth multi-network cardholders can now choose between eftpos and Mastercard when making debit card payments using Samsung Pay.
Switching between services is "a simple toggle" according to eftpos.
Using eftpos avoids the surcharge imposed by some retailers for transactions via the credit card networks.
"eftpos also has the added convenience of real time balances, helping consumers stay on top of their holiday spending," said eftpos CEO Stephen Benton.
"At a time of year when Australians can really benefit from the added conveniences of a true wallet replacement in the palm of their hand, we hope this will save CBA customers precious time when going shopping."
The use of eftpos for mobile payments has been steadily rising during 2020, he added.
Commonwealth Bank general manager of everyday accounts retail FX Rohan Ritchie said "Whist coronavirus has led to a decline in cash, we are seeing that more than ever, Australians are choosing to adopt digital wallets.
"We're excited to be able to provide increased choice through enabling eftpos transactions for many of our customers utilising Samsung Pay."
There is a small wrinkle for existing users. CBA customers who loaded their multi-network debit cards onto Samsung Pay before 9 December will need to update to the latest version of Samsung Pay and re-load their cards in order to see the eftpos payment option.