25 CFR 141.19: Check cashing.

(a) A reservation business may give a fully negotiable check in addition to U.S. currency when cashing a draft, check or money order. A reservation business may not give scrip, credit or other substitute for U.S. currency when cashing a draft, check or money order.

(b) A reservation business owner or employee may advise a customer cashing checks, money orders or drafts of the amount due on the customer's credit accounts, pawn accounts or any other obligation the customer owes to the business, but in no event may the owner or employee withhold the proceeds of the check, money order or draft from the customer on the basis of existing credit obligations.