Believe me, I’d use much more colorful language if this wasn’t a family-friendly website. This exercise was a lot more tedious than I imagined. Again, the rules applied in general terms only. There were also a handful of odd-numbered highways that crossed time zone boundaries too and muddied the construct a bit. Even-numbered Interstates run roughly west to east across the nation with the 2-digit numbering increasing from south to north. I didn’t reverse the order just to be obstinate. That was also the reason why Interstate numbers on the spreadsheet and the lists below were ordered from large to small (I-94 to I-8). The spreadsheet layout mimics the geographic footprint of the United States in rough terms, for example I positioned Idaho at the top-left (northwest) and Florida at the bottom-right (southeast). Others may prefer the even more detailed Google spreadsheet with links that I prepared. It’s not very useful in its present scaled down version that is included for illustrative purposes. Readers will want to open this map in another tab or window. I even collected the lat/long coordinates so travelers (OK, maybe just me…) could drop the waypoints into their GPS receivers and know exactly where time changes happen well in advance. However some of us like to be hyper-prepared before embarking on a journey. Yes, I understand that mobile phones and other networked devices grab time changes automatically without human intervention from nearby cell towers as someone drives merrily down the highway. Hopefully others will find this compact reference useful too. I didn’t see it so I decided to create my own. Maybe there’s one out there hidden away in a lonely corner of the Intertubes. I’m going to do that myself soon on my upcoming trip and I couldn’t find a comprehensive resource either. I’ve noticed a lot of search engine queries lately seeking additional information about points along US Interstate Highways where travelers cross from one time zone into another.

Us time zone map current times