Surcharges are permitted in some states.
Colorado law recently changed permitting merchants to pass on the actual cost of processing, except for cash, check and debit payments.
https://colorado.public.law/statutes/crs_5-2-212
This law overrides any prior contractual agreements with banks/processing companies that prohibit surcharges. This is previously how MasterCard and VISA coerced merchants into absorbing the processing fee, by contractually requiring credit same as cash pricing.