On cold filling of pressure containers the filling gas is cooled before introduction into the pressure container to be filled. On completion of the filling process the pressure container is sealed in a pressure-tight manner. As the gas warms up the pressure in the pressure container rises rapidly. According to the invention, the pressure container is cooled before the introduction of the filling gas. The filling gas cools rapidly by means of heat transfer to the pressure container, whereby the filling capacity of the pressure container is considerably increased. Said method is particularly suitable for the filling of small tanks, in particular, for gas-driven vehicles and fuel-cell systems.