Article 121 Political Constitution of the United Mexican States
Fifth Title. On the States of the Federation and of Mexico City
Current text · last reform published in the Official Gazette of the Federation (DOF) on 2 June 2026
In each federal entity full faith and credit shall be given to the public acts, records and judicial proceedings of all the others. The Congress of the Union, by means of general laws, shall prescribe the manner of proving said acts, records and proceedings, and their effect, subject to the following bases:
I.The laws of a federal entity shall only have effect in its own territory and, consequently, may not be obligatory outside of it.
II.Movable and immovable property shall be governed by the law of the place of its location.
III.The judgments (sentencia) rendered by the courts of a federal entity on real rights or immovable property located in another federal entity shall only have executory force in the latter, when its own laws so provide.
Judgments on personal rights shall only be executed in another federal entity when the person condemned has submitted expressly or by reason of domicile to the justice that rendered them, and provided that such person has been personally summoned to appear in the proceeding.
IV.The acts of civil status in accordance with the laws of a federal entity shall have validity in the others.
V.The professional licenses issued by the authorities of a federal entity in accordance with its laws shall be respected in the others.