Commonwealth Bank customers can now use their iPhones for tap-and-go payments, in a change that may up the pressure on the remaining big banks to follow suit and cave in to the tech giant.

The country's biggest bank on Wednesday started providing Apple Pay, a service that allows customers to make contactless payments with their phones, as well as streamlined purchases in apps and on the web.

CBA is launching Apple Pay in response to demand from customers. Credit:Josh Robenstone

Until CBA announced its deal with Apple last month, ANZ Bank had been the only big four bank to provide the service in Australia, after CBA, Westpac and National Australia Bank reached a stalemate in talks with Apple in 2016 over access to hardware on the phone.

The three big banks had wanted to strengthen their bargaining position by launching a collective boycott of Apple Pay, but this request was rejected by the competition watchdog in 2017. Apple also takes a cut of the fees banks receive from credit card companies, known as interchange fees.