The article discusses one of the many transport services provided by serfs for the benefit of the ruler and his officials on the lands of the former Polish state. Podvoda (the podwód) consisted in supplying horses, which were used mainly by the king with his wife. They were also used persons to whom one of them ordered to supply podvoda horses (e.g. royal messengers), while the obligation to provide this kind of obligation was often changed into a kind of rent (known podwodne or podwodnie) paid in exchange for the obligation to carry out and provide podvodas. The analysis conducted by the Author concerns the issues related to legal regulations in the field of the podvoda duty in the light of the provisions of 16th and 17th century universals and constitutions contained in the collection of the oldest laws of the Polish state.