The nation's banks will send debit cards directly to more than 500,000 Australians who don't have them and have previously relied on cash or EFTPOS payments.

Some half a million Australians who don't have debit cards and can't use contactless payments for groceries will now be sent the cards by their banks.

The Mastercard or Visa cards are being issued on the basis that these mainly elderly Australians, many of whom still use passbooks, don't have to use them.

But the banks are voluntarily offering the cards, which will be linked to accounts, to give these customers the option of using a debit card to shop if they are isolating or in quarantine.

Australian Banking Association CEO Anna Bligh said these customers are usually aged 70 years or more, regularly use passbooks and like to withdraw cash from their bank branches to pay for bills and groceries.

But that's not an option now because the spread of the coronavirus has prompted shops and businesses to reject cash or pin payments in favour of contactless tap-and-go cards.

"These cards will be sent out to people with instructions that the banks have people on the other end of the line to help," Ms Bligh told ABC TV on Wednesday.

But she also urged family members to be aware, in case their relatives aren't quite sure when they check the mail, and to try to help them through the card activation process.

Customers do not have to pay anything to use the cards.