On Sunday, March 9, 2025, Mexico will carry out its traditional daylight saving time (DST) change, impacting primarily regions near the U.S. border. This change, which involves advancing clocks by one hour at 2:00 AM — allowing folks to set their clocks to 3:00 AM — aims to optimize natural light utilization during periods of high solar radiation, thereby contributing to energy savings. While DST has been practiced globally for decades, it has not been uniformly applied across Mexico since 2022, when restrictions were placed on its implementation, confining it to specific northern areas.
The new DST schedule is applicable to certain municipalities within five key states, intended to align their time with the United States. The municipalities affected include:
- Baja California: Tijuana, Rosarito, Tecate, Ensenada, and Mexicali.
- Chihuahua: Coyame del Sotol, Manuel Benavides, Janos, Ascensión, Ciudad Juárez, Praxedis G., Guerrero, and Guadalupe.
- Coahuila: Acuña, Allende, Guerrero, Hidalgo, Jiménez, Morelos, Nava, Ocampo, Piedras Negras, Villa Unión, and Zaragoza.
- Nuevo León: Anáhuac.
- Tamaulipas: Nuevo Laredo, Guerrero, Mier, Miguel Alemán, Camargo, Gustavo Díaz Ordaz, Reynosa, Río Bravo, Valle Hermoso, and Matamoros.
The decision to continue observing DST solely within these border regions is driven by their close commercial and administrative ties to the United States. The synchronized time helps facilitate commercial operations and services between the two countries, minimizing discrepancies in product and service exchanges.
Despite years of adapting to the DST shift, many residents still express confusion about its application. Following 26 years of DST practice, the current regulation has led to questions concerning which states still observe this time change. Particularly, many people wonder whether to advance or delay their clocks. Given the shift starts this Sunday, it is important for individuals residing within the affected municipalities to set their clocks forward one hour before going to bed on the evening of Saturday, March 8, 2025. This mechanical adjustment aligns their schedules with regions to the north.
Since 2022, much of Mexico has foregone the DST adjustments. A Presidential Decree established the Law of Time Zones, indicating, “the national territory will have a standard time established according to time zones, with seasonal times applying only to states and municipalities of the northern frontier,” as stated by the federal government. Therefore, notable metropolitan areas such as Mexico City (CDMX) do not observe this time change; they maintain their standard hour throughout the year.
The implementation of DST is seen as beneficial, particularly for municipalities such as Anáhuac, Nuevo León. This locality lies at the north border with the United States, which necessitates aligning business hours for effective cross-border transactions. The jurisdiction spans various regions bordering Tamaulipas and Coahuila, making its synchronization with U.S. hours even more significant.
The seasonal time change will continue until November 2, 2025, when clocks will revert one hour from 2:00 AM back to 1:00 AM. Such adjustments support Mexico's aim to harmonize its time with neighboring states, facilitating smoother economic activities. The practice of DST is underscored by its goal to help businesses maximize daylight hours and thereby reduce electricity consumption during seasons when the sun sets later.
For residents of the border municipalities, remembering to adjust the clocks correctly on the specified date is key. By doing so, they can avoid confusion and continue to benefit from the trade advantages presented by synchronized working hours across borders. Historically, significant economic relationships necessitate these time changes, particularly with the growing trade volume seen between the two countries.
Notably, for municipalities where DST is not applicable, the absence of this adjustment leads to questions about potential future changes. Continuous public dialogues concerning the necessity and practicality of DST adjustments often arise, especially when it seems to diverge across national borders. Such discussions may influence future governmental decisions concerning standardized time policies.
With all of these factors considered, residents of Mexican border towns are urged to prepare for the upcoming time change as they join with their neighbors across the U.S. border. The transition is not only about moving clocks but also about nurturing and enhancing economic ties through synchronized daily living. Observing daylight saving time within these regions emphasizes the importance of connectivity between communities and shared economic goals. So as the sun rises on March 9, let’s make the transition thoughtful and efficient, setting the clocks with intent and precision, and keeping the bonds with our neighbors strong.