Hawaii officials said it will be the first state to conduct medical cannabis sales entirely without cash by October 1. 

Medical cannabis dispensaries in Hawaii will not be allowed to accept cash after the designated date and will require patients to use a debit card payment app called CanPay.

The CanPay app uses a Colorado-based credit union to handle transactions, and already works with cannabis companies in six states where the plant is legal in some form. Patients who don’t have smartphones can create an online account at home and log in using computer tablets at dispensaries.

During the Obama administration, the Justice Department issued guidelines to help banks avoid prosecution when dealing with cannabis businesses. Most banks view the rules as hard to follow and fear federal charges including drug trafficking.