Bitcoin has a new use in Poland: T-Mobile now lets customers buy phone credits with the cryptocurrency.

In late February, T-Mobile announced a new Bitcoin trial that would allow customers to prepay for mobile minutes with Bitcoin, according to Coindesk. The program is the result of a partnership with Warsaw-based Bitcoin processor InPay. Since then, the company has rolled out the InPay payment option on its site along with instructions for how to use Bitcoin to prepay for minutes. The company will offer customers who add minutes with Bitcoin 20 percent more calling credits as an incentive.

This is T-Mobile’s first foray into crypto-payments.