Note From Julie: Time Zone Abbreviations Are More Important than You Think

Mar 8, 2018 | Organization

Daylight Saving Time begins in the U.S. this weekend. That means for the next eight months, our time zone abbreviations also need to change if we want our meeting invites to be accurate.
What am I talking about? Let me explain.

We are currently operating in Standard Time. In the United States, that means the time zone abbreviations for our meetings have been EST (Eastern Standard Time), CST (Central Standard Time), MST (Mountain Standard Time), and PST (Pacific Standard Time).

When Daylight Saving Time beings, the correct time zone abbreviations will be EDT (Eastern Daylight Time), CDT (Central Daylight Time), MDT (Mountain Daylight Time), and PDT (Pacific Daylight Time). The S changes to D to indicate the change from Standard Time to Daylight Saving Time.

Why does this matter? Because not all parts of the world – or even the U.S. – switch to Daylight Saving Time. Hawaii and most of Arizona do not switch. And there are many countries around the globe that do not use Daylight Saving Time either. Even those places that do observe Daylight Savings Time don’t all switch at the same time. This makes time zone abbreviations crucial, especially when you have participants from multiple time zones.

Here are two examples of how this applies:

Example 1: EST is never the same as EDT.

Last summer, while Daylight Saving Time was in effect in the U.S., I was supposed to present an online training event for an international client at 6 p.m. GMT (Greenwich Mean Time). I live in the Eastern Time Zone in the United States. If you plug 6 p.m. GMT into any time zone converter app, it will tell you that is 2 p.m. EDT (Eastern Daylight Time). However, the event organizers had advertised the event for 1 p.m. EST (Eastern Standard Time).

I was on time for the event at 2 p.m. EDT. However, most of the people from my region of the world who normally joined that online training event were not there because they assumed it was happening at 1 p.m. EDT – even though the abbreviation said EST. The event organizers could have avoided a lot of confusion and increased their event attendance significantly if they had published their event with the correct time zone abbreviation.

Here’s another application of this concept for meetings: One of my team members is in Mountain Standard Time. She stays in that time zone all year around because she’s in a part of Arizona that doesn’t switch at all. So if I send a meeting invite for the team call at 1 p.m. MDT (Mountain Daylight Time) and she is actually in Mountain Standard Time, then it occurs at 12 p.m. MST (Mountain Standard Time) because she doesn’t “spring forward” for Daylight Saving Time.

Example 2: Always publish meeting times with the time zone abbreviation for where the meeting is occurring.

Last fall, I was scheduled to present a webinar for an international association. We were still on Daylight Saving Time in the U.S. The country for the association hosting this webinar had already moved back to Standard Time.

I was nervous about being on the webinar at the right time, so I checked it frequently. With this event, I learned how important it is to publish the time of the event for the time zone in which the event is occurring, with the correct time zone abbreviation. That way when anyone plugs it into a time zone converter, they will know what time to join the event in their own time zone. This is especially important when dealing with companies on the other side of the International Date Line because the meeting may actually occur on the next day.

A few key takeaways here:

  • Learn the time zone abbreviations and how to use them for the time zones you work with the most. If you aren’t sure, look them up!
  • Always set the meeting time on your calendar invites for the time the meeting is scheduled to take place in the originating location, and let the calendar convert it to the respective time zone of each recipient. Then if the organizers update the time, your attendees get the updates, which is also important.
  • Include the time of the meeting, with the time zone abbreviation in the originating location, in the subject line of your meeting invite so all invitees and their assistants can see it and do the manual conversion, if needed. It helps tremendously. If you update the meeting time, though, you need to remember to update it on both the invite and in the subject line.

The bottom line is to never assume which abbreviation is accurate if you don’t know for sure. Check it. Download the time zone convertor apps or save the links to your computer so you can check and get it right – every single time!

This week, our feature article explains why it’s crucial that you use correct time zone abbreviations in your correspondence. Our Facebook, Twitter, and LinkedIn pages are also full of time zone tips and tricks to help you get where you need to be, when you need to be there!

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