Supermarket kiosk company Coinstar has added Coinme bitcoin kiosk functionality to 5,000 change-sorting machines across the U.S.

The service is now available in nearly 25% of Coinstar's total kiosk fleet and in 40 U.S. states, according to figures provided by Neil Bergquist, chief executive of Coinme. Coinstar change-counting machines are located in supermarkets, gas stations and convenience stores around the country.

"There is a Coinstar kiosk located within five miles of 90% of the American population," he told CoinDesk. "So the collective opportunity here is to be able to give the majority of the U.S. population access to digital currencies."

Over the last year in particular Coinme has made in-roads in some of the farthest-flung U.S. locales. It was admitted to Hawaii's digital currency sandbox in August along with 11 other cryptocurrency exchanges. Bergquist said Coinme is the only participant to offer cash-to-crypto services.

Also in the recent Coinme/Coinstar expansion: Georgia, Nevada, New Mexico, Ohio, Oregon, Maryland, West Virginia, Delaware and Rhode Island. Bergquist said locations have grown 65% since March.

See also: Coinstar Plans Massive Expansion of Coinme Bitcoin ATMs as Usage Spikes 40%

The fast-growing kiosk network has allowed Coinme transaction volume to soar; bitcoin sales are up 650% year over year. Bergquist predicts yet higher numbers as more states give Coinme the go-ahead to launch operations.