Method for filling a tank with pressurized hydrogen via a filling station comprising at least one buffer container and a fluid circuit connected to said at least one buffer container, the circuit of the filling station comprising a first end connected to at least one source of hydrogen gas, the circuit comprising a second end fitted with a transfer pipe intended to be connected removably to the tank that is to be filled, the method involving a step of cooling the hydrogen supplied to the tank by transferring negative calories between a cold source and the hydrogen, the method being characterized in that it comprises a step of purifying the hydrogen supplied by the source in a purification member before transferring it to the at least one buffer container, and in that it comprises a step of transferring negative calories from said cold source to the hydrogen before and/or during the purification step.