A method for operating a dosing device for metering an additive to an exhaust-gas treatment device includes determining a dosing amount of additive required by the exhaust-gas treatment device in step a). Subsequently, in step b), an operating mode for the dosing device is determined by carrying out at least steps b.1) and b.2). In step b.1), at least one characteristic operating value of at least one component of the dosing device is provided being definitive of a degree of aging of the dosing device. In step b.2), an operating mode for the dosing device is set in dependence on the characteristic operating value from step b.1). In step c), the dosing device is operated with the set operating mode so that the dosing amount required in step a) is supplied to the exhaust-gas treatment device. A motor vehicle having a dosing device is also provided.