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Anyone preparing to live, work, or study in the United States quickly runs into a detail that seems trivial but disrupts entire routines: the twice-yearly clock shift known as Daylight Saving Time. Twice a year, millions of clocks spring forward or fall back one hour, altering work schedules, flights, business contracts, and even the biological rhythms of those who have just arrived in the country. Understanding how the system works prevents professional missteps and eases cultural adjustment.
Daylight Saving Time has existed in the United States since the Energy Policy Act of 1966 (Uniform Time Act), with adjustments made in 2007 that extended the period by four weeks. The current rule is straightforward: clocks move forward one hour on the second Sunday in March and return to standard time on the first Sunday in November. In 2026, that means DST began on March 8 and ends on November 1, always at 2:00 a.m. local time.
Who Observes It — and Who Doesn’t
Although most of the fifty states adjust their clocks, there are notable exceptions. Hawaii never adopted the system, arguing that its proximity to the equator makes the change irrelevant. Most of Arizona also opts out, with the notable exception of the Navajo Nation, which observes DST for administrative reasons. The territories of Puerto Rico, the U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands also remain on standard time year-round.
For those working in distributed teams or with clients across different regions, this creates communication windows that open and close according to the calendar. A meeting scheduled for 2:00 p.m. in New York may be three hours away from a colleague in Phoenix for much of the year — and four hours away in other months. Professionals who relocate to the United States often set up two time zones in their corporate calendar during the first months of adjustment.
Physiological Impact in the First Days
Medical literature is consistent about the effect of clock changes on the body. Losing an hour of sleep in March produces what researchers call social jet lag: decreased productivity, difficulty concentrating, and a statistical increase in traffic accidents in the first forty-eight hours after the transition. Studies published in journals such as Current Biology and the American Journal of Cardiology associate the start of DST with a temporary increase in cardiovascular events and depressive episodes.
Those who arrive in the United States near the transition date face a double disruption: the time-zone shift from their home country adds to the country’s internal clock change. Sleep medicine specialists recommend adjusting the cycle gradually by shifting bedtime fifteen minutes per day during the preceding week. Morning exposure to natural light accelerates circadian rhythm synchronization and reduces prolonged fatigue.
Impact on Work and Business
Companies with global operations must reschedule meetings, routing systems, and calendar tools around DST dates. Brazil, which abolished daylight saving time in 2019, and most Latin American countries go through periods when the time difference with New York fluctuates between one and two hours depending on the month. The European Union still maintains its own seasonal adjustment on different dates than the U.S., creating windows of up to three weeks when transatlantic time zones fall out of their usual alignment.
For professionals in technology, finance, and logistics, the transition requires checking servers, task schedulers, and contracts with time-specific clauses. Modern systems update the clock automatically, but integration failures with legacy APIs still generate corporate incidents every March and November.
The Energy-Saving Argument Under Scrutiny
The historical justification for DST was energy conservation. The logic assumed that more natural light in the late afternoon would reduce artificial lighting consumption. More recent research from the U.S. Department of Energy and academic studies — such as the one by Matthew Kotchen and Laura Grant published by the NBER in 2008 — show that the actual effect is marginal or even negative, since air conditioning use during longer, warmer afternoons can negate any gains. In colder states, morning heating offsets the savings from reduced evening lighting.
The argument that holds up best today is the lifestyle one: retail, restaurants, parks, and outdoor activities gain extra hours of daylight after the workday, with documented effects on service-sector revenue. Farmers and workers who begin their shift before dawn, however, complain about extended darkness during the transition months.
The Sunshine Protection Act Debate
In March 2022, the U.S. Senate unanimously passed the Sunshine Protection Act, a bill that would make daylight saving time permanent nationwide. The House of Representatives, however, never brought the measure to a vote, and the bill expired at the end of that congressional term. Versions reintroduced in 2023 and 2025 also failed to advance.
The debate resurfaced in December 2024, when President Donald Trump posted on social media that the Republican Party would work to eliminate DST. In April 2025, Trump softened his position, stating that the issue divides the country evenly and would not be an immediate legislative priority. Medical organizations such as the American Academy of Sleep Medicine advocate for permanent standard time — not permanent daylight saving time — arguing that the morning solar rhythm is healthier than extended evenings.
Pending a federal decision, several states have passed conditional legislation. Florida, California, Washington, Oregon, Tennessee, and more than a dozen other states have enacted laws that would adopt permanent DST, but all require congressional authorization to take effect.
How to Prepare When You Arrive
For those in the immigration process, planning academic exchanges, or accepting a job offer requiring relocation to the United States, there are practical steps that reduce friction during the first transition. Set devices to automatic time zone updates. Manually confirm the times of flights, consular appointments, and medical visits in the days following the change. Notify family members and clients in other countries about the transition window, especially in the first two weeks after the shift.
International students should check with their university whether exams, submission deadlines, and online tutorials reflect the updated time zone. Professionals on work visas such as H-1B, L-1, or O-1 should coordinate with Human Resources on the scheduling transition for meetings with headquarters on other continents. Families in the Green Card process awaiting interviews at consulates or USCIS offices should confirm the local time of each appointment, as older devices may not update correctly.
Daylight Saving Time is both a cultural curiosity and an operational detail that can trip up anyone who underestimates its reach. Knowing the dates, the states that opt out, and the current state of federal legislation puts newcomers one step ahead in adapting to American daily life.
Victoria Harper
Editor-in-Chief
Leading journalism and editorial content at Visto n’ Visa, Victoria helps make immigration topics clear, trustworthy, and easy to understand. Her focus is on delivering useful, human, and relevant content for people exploring new paths abroad.
