US Time Zones: Not 6, Heres the Real Number

In 2019, the Bureau of Transportation ... Subtitle A, Part 71 - Standard Time Zone Boundaries. Currently the United States and its territories have 9 time zone boundaries: Atlantic, Eastern, Central, Mountain, Pacific, Alaska, Hawaii–Aleutian, Samoa, and Chamorro....

Before U.S. and Canadian railroads standardized time zones in 1883, there were more than 144 local times in North America! But, the changes didn’t stop then. In 2006, when eight counties in Indiana changed time zones, BTS contributed the maps used by USDOT to authorize the change.

The National Institute of Standards and Technology - Time and Frequency Division maintains the standard for frequency and time interval for the United States, provides official time to the United States, and carries out a broad program of research ...

Official websites use .gov A .gov website belongs to an official government organization in the United States. Secure .gov websites use HTTPS A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites. U.S. Naval Observatory ... If you are deaf, hard of hearing, or have a speech disability, please dial 7-1-1 to access telecommunications relay services. The U.S. Department of Transportation (DOT) oversees the Nation's time zones.

Every city in the United States used a different time standard so there were more than 300 local sun times to choose from. Time zones were therefore a compromise, relaxing the complex geographic dependence while still allowing local time to be approximate with mean solar time. Railroad managers ...

On November 18, 1883, United States and Canadian railroads instituted standard time in time zones. Before then, time of day was a local matter, and most cities and towns used some form of local solar time, maintained by some well-known clock (for example, on a church steeple or in a jeweler's ...

This is a list of the time offsets by U.S. states, federal district, and territories. For more about the time zones of the U.S. see time in the United States. Most states are located entirely within one time zone. However, some states are located in two time zones for geographic, socio-political, ...

The territory of the 50 US states extends over eight standard time zones, from UTC (GMT) −4 to −11 hours. There are six designated US time zones; and there are four time zones in the contiguous USA.

The contiguous US has 4 standard time zones. In addition, Alaska, Hawaii, and 5 US dependencies all have their own time zones. As neither Hawaii nor the 5 dependencies use Daylight Saving Time (DST), there are only 6 corresponding DST time zones. Since Howland Island and Baker Island constitute the world's westernmost landmasses in relation to the International Date Line, making them the last places on Earth where any date exists, they are sometimes assigned a theoretical 12th time zone called Anywhere on Earth (AoE).