So far, $20s have been a big problem, they say.
Vendors are requesting more time to make the necessary changes in machines, the Canadian Broadcasting Corp. reported Monday.
The $20s already released don't work in their machines, vendors say. New $5s and $10s are also to be put into circulation.
"We needed months, more time to get ready," said Aire Koifman, president of the Canadian Automatic Distribution Association.
Francois Bastien, the owner of vending machine company Vendomax, said he spent much of last year upgrading his machines to take Canada's new coins. Now he has to deal with the bills.
The software on many of his machines was upgraded, but Bastien said a lot of the machines had to be replaced. Adjusting to the new $20 alone has cost his company about $100,000, he said.
Costs for the vending industry to replace or upgrade its soft drink machines, self-service checkouts, casino slots and other devices that accept bank notes will probably run about $250 million, Bastien said.
The Bank of Canada said in a statement it had provided vending machine manufacturers with sample bills and gave them six months to upgrade before the new bills go into circulation.