Daylight Saving Time & Business Hours: What Changes
A clock-change weekend adds another question to your hours check: which local time will apply when you arrive? Start with the destination, the date and the service you need. That is especially helpful for an overnight visit or a trip between places that handle daylight saving time differently. You can then compare the posted opening time with the clock you will actually be using, without guessing from the amount of daylight outside.
How the Clock Change Works
Under the rules described by the National Institute of Standards and Technology’s daylight saving time guide, daylight saving time begins at 2:00 a.m. local time on the second Sunday in March. The clock moves directly to 3:00 a.m., leaving one fewer hour in that day. It ends at 2:00 a.m. local time on the first Sunday in November, when the clock moves back to 1:00 a.m. and that hour repeats.
In 2026, the change to daylight saving time took place on March 8, and the return to standard time is November 1. Both changes occur at 2:00 a.m. local time. Think of these as changes to the clock reading: moving forward in March and back in November. They do not tell you whether a particular business has changed its opening schedule, so verify that separately.
A Short History
Daylight saving time was formally introduced in the United States in 1918. The Energy Policy Act of 2005 extended its duration, with the changed rules taking effect in 2007. NIST describes the resulting daylight saving period as 238 days, or about 65% of the year, an extension of about one month.
NIST explains that advancing the clock shifts an hour of daylight from morning to evening; returning to standard time shifts it back toward morning. For planning an errand, separate that daylight shift from the opening time you have confirmed. The useful question is when you can use the service on the relevant date, even if the morning feels darker or the evening feels earlier than you expect.
Where Clocks Don’t Change
Hawaii, American Samoa, Guam, Puerto Rico and the Virgin Islands do not observe daylight saving time. Neither does most of Arizona, but the Navajo Indian Reservation in Arizona does observe it. Keep that exception in mind rather than treating every Arizona destination alike. Daylight saving time and time zones are regulated by the U.S. Department of Transportation; NIST explains and follows those rules when distributing time information.
If your trip or conversation connects an observing location with one that does not observe daylight saving time, check the relationship for the actual date. Use the destination’s time zone when confirming an opening or arranging a conversation. A remembered difference from another season is a poor substitute for that check.
What It Means for Opening Hours
Read a posted schedule in the destination’s local time, and confirm any clock-change exception with the location. For an early opening, write down the date as well as the time. For a remote conversation, identify whose local clock the agreed time refers to. Our store hours guide explains how to check the particular location and the counter you need.
An overnight visit deserves a more precise question. In March, the clock skips from 2:00 to 3:00; in November, the 1 a.m. hour occurs twice. If a service window touches those hours, ask how the location handles the transition. Even for a business described as operating around the clock, confirm the particular service rather than inferring its availability from that description.
Before relying on a device, check that its displayed time and selected time zone match the destination. Compare any clock you will use for departure with the local time you confirmed. If the readings disagree, resolve the difference before working backward from an opening or closing time.
A Quick Clock-Change Checklist
- Choose the date. Check whether your visit is before, during or after the transition.
- Identify the destination. Confirm whether it observes daylight saving time and which time zone it uses.
- Check the service. Verify the counter or opening window that matters to your trip.
- Clarify overnight times. Ask about any window that overlaps the skipped or repeated hour.
- Compare your clocks. Make sure the time you are using agrees with the destination’s local time.