The very simple reason why Tennessee doesn’t do Daylight Saving Time is actually a misconception—Tennessee does observe Daylight Saving Time. The two U.S. states that truly do not observe Daylight Saving Time are Hawaii and most of Arizona.
Hawaii does not observe Daylight Saving Time because its location near the equator means daylight hours remain relatively constant throughout the year, so there is little benefit to changing clocks. Arizona, aside from the Navajo Nation, opts out due to its desert climate where extending daylight hours into the hot evenings would increase energy use for cooling rather than decrease it.
So, Tennessee follows daylight saving like most states, while Hawaii and most of Arizona are the exceptions that do not observe it.
Sources
(https://economictimes.com/news/international/us/when-daylight-saving-time-2025-fall-back-date-end-states-observe-what-reason-us-states-territories-do-not-follow-how-to-prepare/articleshow/123099184.cms)
(https://www.jagranjosh.com/us/trending/us-time-changes-1860001105)
(https://thehill.com/homenews/nexstar_media_wire/5184764-two-states-didnt-spring-forward/)
(https://en.wikipedia.org/wiki/Daylight_saving_time_in_the_United_States)
(https://www.usatoday.com/story/news/nation/2025/09/08/when-daylight-saving-time-2025/85821111007/)
