The US is currently in:
Except for Arizona and Hawaii

Arizona does not observe Daylight Saving Time and stays on Mountain Standard Time (MST) year-round (UTC−7). This means that during Daylight Saving periods elsewhere (March to November), Arizona time aligns with Pacific Daylight Time (PDT). An exception is the Navajo Nation in northeastern Arizona, which does observe Daylight Saving Time, making it one hour ahead of the rest of the state during those months. Understanding this helps avoid confusion when coordinating with Arizona, as the time difference may not be what you expect based on your own location’s observance of Daylight Saving Time.

Daylight saving time (DST) begins on the second Sunday of March and ends on the first Sunday of November.