How to accurately refer to time zones (Correcting a common mistake)

When’s the last time your got an email saying something like “Ok, I will call you at 2:00 pm EST”?

If it’s been within the last couple of months, there’s an error.

EST = Eastern Standard Time
CST = Central Standard Time
MST = Mountain Standard Time
PST = Pacific Standard Time

I’m sure this isn’t news to you… but this probably is:

EDT = Eastern Daylight Time
CDT = Central Daylight Time
MDT = Mountain Daylight Time
PDT = Pacific Daylight Time

…these are the time zone abbreviations for use when it’s Daylight Savings Time. So, technically, each time somebody talks about EST, CST, MST, or PST during the summer months they are probably one hour off from saying what they are actually meaning. I used to make this mistake all the time until I was corrected earlier this year by someone in the know.

Why the difference?

Some areas don’t observe daylight savings time, so when using time zone abbreviations as they were intended, coordinating times with people in these areas becomes possible with the two sets of abbreviations.

My recommendation

Many people aren’t familiar with EDT, CDT, MDT, & PDT, so I don’t use them. Instead, I simplify things by using ET, CT, MT, & PT. There aren’t too many cities that don’t observe daylight savings time… and when dealing with people in those areas, they’ll probably know how sync up with your time zone.

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