Mexico uses four time zones, and since October 30, 2022, most of the country keeps the same time all year. Mexico City, Guadalajara and Monterrey stay at UTC−6 in January and in July. Cancún stays at UTC−5, Los Cabos and Mazatlán at UTC−7. The only places that still move their clocks are Baja California and a list of border municipalities, and they do it on US dates, not Mexican ones.

That creates an odd effect for anyone scheduling across the border. Mexico’s clocks no longer move, but the gap between Mexico and the United States still changes twice a year, because US clocks do. Mexico City matches Chicago from November to March and Denver from March to November.

Four zones fixed to four meridians

The current rules come from the Ley de los Husos Horarios en los Estados Unidos Mexicanos, published in the Diario Oficial de la Federación on October 28, 2022. The law recognizes four reference meridians, 75°, 90°, 105° and 120° west of Greenwich, and assigns every state to one of them:

• Zona Sureste (UTC−5): Quintana Roo only, including Cancún, Playa del Carmen, Tulum and Chetumal.
• Zona Centro (UTC−6): most of the country, including Mexico City, Jalisco, Nuevo León, Yucatán and, since 2022, most of Chihuahua.
• Zona Pacífico (UTC−7): Baja California Sur, Sinaloa, Sonora and Nayarit, except the municipality of Bahía de Banderas.
• Zona Noroeste (UTC−8): Baja California.

Two details on that list trip up visitors. Bahía de Banderas, the Nayarit municipality at the southern end of the Riviera Nayarit that includes Nuevo Vallarta, Bucerías, Punta de Mita and Sayulita, is carved out into Central time so that it matches Puerto Vallarta across the state line in Jalisco. And Yucatán is not on Cancún time: Mérida, Valladolid and Chichén Itzá all run on UTC−6, so a day trip from Cancún to the pyramids crosses a time zone boundary, and the site’s opening hours are in the earlier Central time.

Current local time for major cities is on our time in Mexico page.

What the 2022 law ended, and why

Mexico adopted nationwide daylight saving time, the horario de verano, by decree in 1996. The stated goal was to save electricity by making better use of evening daylight, and close economic ties with the United States made shared clock changes convenient. For most of the country it ran from the first Sunday in April to the last Sunday in October. The new law abolished it: it passed the Senate on October 26, 2022, was published two days later and took effect on Sunday, October 30, 2022, the date of that year’s final fall-back. Everywhere outside the border strip, that last shift back became permanent.

The government’s case rested on two claims. The first was energy. According to the Secretaría de Energía, DST saved 537 gigawatt-hours in 2021, about 0.16% of national electricity consumption of roughly 327,000 GWh, worth about 1,138 million pesos. Energy Secretary Rocío Nahle said savings had peaked at 1,347 GWh in 2013, and the ministry noted that savings had shrunk from 0.62% of consumption in 1996. Its explanation was that efficient appliances and modern lighting had already captured most of what DST once saved. The second claim was health: Health Secretary Jorge Alcocer argued that changing the clocks twice a year disrupts sleep, and the government cited a national survey by the Secretaría de Gobernación in which 71% of respondents opposed DST.

Both claims deserve some care. The energy numbers are the government’s own estimates, and most research linking clock changes to sleep loss, accidents or heart attacks comes from observational studies in the United States and Europe rather than from Mexico. Opponents in the Senate argued the other side, that brighter evenings reduce crime and encourage outdoor activity. The debate in Mexico mirrored the one that happens wherever daylight saving time comes up.

What stands out is the direction Mexico chose. A country that abolishes clock changes has to decide which time to keep. Mexico kept standard time, the position favored by the American Academy of Sleep Medicine, which argues that permanent standard time better aligns the body clock with the sun. The US Senate went the other way in March 2022, passing a bill for permanent daylight time that never became law. By our calculation, from Mexico City’s longitude and the equation of time, solar noon there now falls between about 12:20 p.m. and 12:51 p.m. across the year; under summer DST it came an hour later.

The border strip that still runs on American dates

Article 5 of the law keeps a seasonal time only for the northern border, and it copies the US schedule exactly: clocks spring forward at 2:00 a.m. on the second Sunday of March and fall back at 2:00 a.m. on the first Sunday of November. In 2026 those dates were March 8 and November 1. In 2027 they are March 14 and November 7.

The list is specific. All of Baja California changes, which keeps Tijuana and Mexicali on the same time as San Diego. In Chihuahua, the changes apply in Juárez, Janos, Ascensión, Praxedis G. Guerrero, Guadalupe, Ojinaga, Coyame del Sotol and Manuel Benavides. In Coahuila, the list includes Acuña, Piedras Negras and nine neighboring municipalities. In Nuevo León, only Anáhuac changes. In Tamaulipas, the list includes Nuevo Laredo, Reynosa, Matamoros and seven more. Each one follows the clock of its counterpart across the border.

Since 2022, the only Mexicans who still change their clocks do it on the US calendar. The interior keeps standard time all year; the border follows its American neighbor. worldtimedata

Because the strip is narrow, a single drive can cross the line. Nuevo Laredo changes its clocks; Monterrey, about 140 miles south by road in Nuevo León, does not. In summer, a driver heading from Laredo, Texas to Monterrey sets the watch back an hour on the way, even though the trip never leaves Mexico’s Central zone. The same happens between Piedras Negras and Saltillo in Coahuila.

Ciudad Juárez spent most of November 2022 an hour off

The original law had a gap. Before 2022, Chihuahua used Mountain time (UTC−7, with DST in summer). The new law placed the whole state in the Central zone at UTC−6 and left Juárez out of the border exception. The tz database, which phones and computers use to set local time, recorded that on October 30, 2022 Chihuahua would move to year-round UTC−6, so its clocks did not change that day at all.

The trouble came a week later. El Paso fell back to UTC−7 on November 6, 2022, while Juárez stayed at UTC−6. For more than three weeks, the two halves of one metropolitan area, linked by bridges used by daily commuters, sat an hour apart. Congress approved an amendment on November 24; it was published on November 29 and took effect on November 30. It put Juárez and four neighboring municipalities on Mountain time with US rules, matching El Paso, and Ojinaga and two others on Central time with US rules, matching Presidio, Texas. To handle it, the tz database created a new zone, America/Ciudad_Juarez, split off from America/Ojinaga. It is a textbook case of why an IANA time zone is named for a city rather than an offset: two Chihuahua border cities now follow different rules.

The first version of the change was also cut close. The tz database release that encoded the new law, 2022f, went out on the evening of October 28, 2022, less than two days before the clocks were due to change, which left operating system and software vendors almost no time to push the update.

Sonora and Arizona already had the answer

Sonora sits on UTC−7 and dropped DST in the late 1990s, only a couple of years after Mexico adopted it, to stay aligned with Arizona, its main trading partner. Most of Arizona has kept year-round standard time since 1968, for reasons laid out in why Arizona skips DST. As a result, Nogales, Arizona and Nogales, Sonora show the same time every day of the year, and neither side needed to change anything in 2022.

Baja California Sur and Sinaloa now follow the same pattern. Los Cabos and Mazatlán sit at UTC−7 all year, the same as Phoenix. From March to November they also match California; from November to March they are an hour ahead of it.

Cancún moved an hour ahead for the tourists

Quintana Roo is the only state on UTC−5, and that was a deliberate business decision that predates the 2022 law. Congress created the Zona Sureste in December 2014, and it took effect on February 1, 2015. The tourism ministry argued that the change gave visitors more evening daylight on beaches and archaeological sites, and shortened connection times with 8 airports in Canada and 22 in the United States. Before the change, winter sunsets came around 5 p.m. local time. Not everyone agreed: opponents in Chetumal and the Maya zone, far from the resort coast, argued that the change served hotels rather than residents and announced legal challenges.

Quintana Roo stopped changing its clocks when it moved to the new zone in 2015, so in 2022 it had nothing to abolish.

Mexico versus US time, season by season

For interior Mexico, the gap to any US city that observes DST grows by one hour from the second Sunday of March to the first Sunday of November. A 9 a.m. call in New York is 8 a.m. in Mexico City in winter and 7 a.m. in summer. A 9 a.m. call in Chicago is 9 a.m. in Mexico City in winter and 8 a.m. in summer.

Phones handle all of this correctly as long as the time zone is set to a city, such as Mexico City, Cancún or Tijuana, rather than to a fixed offset like “GMT−6”. The risk sits with devices that apply DST rules on their own: an older car clock, hotel alarm or office phone system still programmed with Mexico’s pre-2022 rules can jump an hour on the first Sunday in April, the day most of Mexico used to spring forward.