On June 24, 2019, the government of Mexico published Rule 1.5.1 of the General Rules of Foreign Trade for 2019 in the Diario Oficial.
Rule 1.5.1 establishes the requirement to transmit the value manifest to the Mexican customs authority in a new electronic format through the Ventanilla Unica de Comercio Exterior Mexicano (VUCEM), Mexico’s single window platform for communicating trade information with various government agencies.
Additionally, the requirement to attach documentation supporting evidence of valuation to the value manifest has been delayed.
The enforcement of both requirements will begin December 1, 2019.
The General Rules of Foreign Trade for 2019 may be found in Mexico’s Diario Oficial here:
http://diariooficial.segob.gob.mx/nota_detalle.php?codigo=5563927&fecha=24/06/2019
A translated version may be found here.