The National Party is launching a petition urging Government agencies and assets to abandon plans to end the use of cheques.
Last year Inland Revenue received 420,000 cheques and ACC received 25,000 - a drop of about 20-25 per cent on 2018.
The organisations are joining KiwiBank and NZ Post - which will no longer accept cheques from tomorrow, and ACC no longer accepting cheques from Sunday, March 1.
National's Andrew Bayly said for the people who write cheques "it's a vitally important thing and our Government agencies should be required to accept those".
"This whole thing is about disenfranchising quite a large proportion of the New Zealand population."
Grey Power has also joined the fight, with president Mac Welch said some people are not computer literate or even own computers.
He accused the Government of "forgetting the older people the senior citizens of New Zealand".
Small business owner Chris van den Brink has dyslexia after a stroke three-years-ago and said he needed time for banking - something writing a cheque allowed him to do.
"You can see a group of numbers and you can visualise them and then you go and write them down and they're all back to front," he said.
Mr can der Brink said many other people were in the same boat.
ACC's Phil Riley said only three per cent of their customers paid by cheque.
"We are working closely with those who still pay by cheque to give them us much support as we can to make this change.
"We’re encouraging customers to register for our secure online service, MyACC for Business, to set up and manage their levy payments going forward."
It also comes as a new report by the Citizens Advice Bureau found 10 per cent of clients suffered from "digital exclusion" due to issues such as language barriers and access to technology. It said thousands of Kiwis struggled to access vital services.
Revenue Minister Stuart Nash was not available for comment.