Businesses face an Oct. 1 deadline to implement them.

Those new computer-chip credit and debit cards now being rolled out will cost individual merchants “from the low hundreds to tens of thousands of dollars,” according to an article by the Associated Press. Businesses that continue to use MasterCard, Visa and American Express magnetic-stripe cards after October 1 can be held liable for transactions made with phony chip cards.“This is one of the biggest nightmares merchants are going to face,” says Michael Kleinman, owner of Mason Eyewear in Brickell, FL.

Read more at Associated Press