ASB is to close 23 branches in February next year and reduce the opening hours of another 13 branches.
The bank's branch closures come on top of the nine it did not reopen after the first Covid-19 lockdown.
Craig Sims, ASB's executive general manager retail banking, said the pandemic had accelerated a customer behaviour trend that was already well underway.
"We've made significant investments in our self-service channels in recent years to meet changing customer expectations, but the pandemic quickened the pace of change, challenging us to rethink what customers expect from a bank.
"Our customers are showing us that they want to be free to take care of their everyday banking transactions when and where it suits them, but they expect us to understand their needs and be highly available when they're looking for more specialised guidance and advice."
He said more than 60,000 ASB customers had used the bank's digital and online banking services for the first time this year and its records showed once a customer chose to go self-service they were sticking with it.
It was seeing over 65 year olds switching to digital banking at a higher rate than any other age-group.
Sims said through Covid-19 the bank had learned a lot about how to serve its customers.
"At alert level 4, just 41 of our branches were open and like many businesses, we rapidly mobilised much of the rest of our workforce to work from home, but we never anticipated how successful this would be.
"Ninety six percent of all customer transactions were self-service, which freed up our people to use a mix of telephone, video and online to deliver more specialised guidance and advice to those who really needed it, no matter where in the country they were."
He said staff were able to help almost twice as many customers per day.
"We had examples such as Timaru branch lenders helping Auckland customers with Covid support. We learned that by changing the way we work we can serve more New Zealanders, faster, and in the ways they prefer."
Sims said there would be no job losses as a result of the branch closures.
From March next year it will have 86 branches.
Branch closures will be in Paihia, Auckland's Greenlane, Howick, Constellation Drive, Whangaparaoa, Blockhouse Bay, Dominion Road, Manurewa, Birkenhead, Lincoln Road, St Heliers, Browns Bay, Wyndham, Devonport. The Cameron Road branch in Bay of Plenty, Morrinsville, Havelock North, Taradale, Terrance End, Wellington's Johnsonville and Kilbirnie branches, Canterbury's Ferrymead, and its Queenstown branch.
Those that are reducing hours from March 1 are Dargaville, Kaikohe, Mangere Bridge, Matamata, Te Awamutu, Masterton, Ashburton, Rangiora, Smales Farm, Cambridge, Hawera, Westport and Gore.