The very simple reason why Pennsylvania doesn’t do daylight saving time yet, along with a few other states, is primarily due to the current federal law that mandates the observance of daylight saving time unless a state opts out entirely. Pennsylvania has not officially opted out or adopted permanent daylight saving time, so it still follows the biannual clock changes.
As of now, only two states—Arizona (except the Navajo Nation) and Hawaii—have opted out of daylight saving time and remain permanently on standard time. Arizona chose this because of its hot desert climate, where an extended evening daylight hour would increase energy use for cooling. Hawaii, being close to the equator, experiences little variation in daylight throughout the year, making the practice unnecessary.
States like Pennsylvania, while some legislators have introduced bills supporting permanent daylight saving time or abolition of clock changes, cannot adopt permanent daylight saving time on their own without federal approval. Until Congress acts on legislation like the proposed “Sunshine Protection Act,” states must continue the clock change twice a year if they do not opt out fully.
Thus, Pennsylvania currently follows daylight saving time like most states but has not yet made a permanent decision, unlike Arizona and Hawaii, where federal and local conditions led them to forego the clock changes entirely.
Sources
[1] https://www.visualcapitalist.com/cp/us-states-scrap-daylight-savings-time-change/
[2] 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
[3] https://ddnews.gov.in/en/why-does-trump-want-to-make-us-daylight-saving-time-permanent/
[4] https://en.wikipedia.org/wiki/Daylight_saving_time_in_the_United_States
[5] https://www.timeanddate.com/time/change/usa
