# What happens with Timezones and Daylight Savings Time?

**URL:** <https://community.fibery.io/t/what-happens-with-timezones-and-daylight-savings-time/8961>\
**Category:** Get Help\
**Created:** [June 11, 2025, 6:08am UTC](https://community.fibery.io/t/what-happens-with-timezones-and-daylight-savings-time/8961 "2025-06-11T06:08:44Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![AdVhPkgKad](https://avatars.discourse-cdn.com/v4/letter/a/7993a0/32.png) [@AdVhPkgKad](https://community.fibery.io/u/AdVhPkgKad)\
**Post date:** [June 11, 2025, 6:08am UTC](https://community.fibery.io/t/what-happens-with-timezones-and-daylight-savings-time/8961/1 "2025-06-11T06:08:44Z")

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1. I create an entity with a time of 11:00 for some day in the future.
2. The local timezone changes to account for daylight savings.

Does that record:  
a) Update the displayed time, changing with daylight savings, now out by an hour either way either 10:00 or 12:00 depending on the transition, or  
b) Retain the same time and accounts for the hour difference

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**Author:** ![Chr1sG](https://sea2.discourse-cdn.com/flex020/user_avatar/community.fibery.io/chr1sg/32/3941_2.png) [@Chr1sG](https://community.fibery.io/u/Chr1sG)\
**Post date:** [June 11, 2025, 7:35am UTC](https://community.fibery.io/t/what-happens-with-timezones-and-daylight-savings-time/8961/2 "2025-06-11T07:35:42Z")

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If you set a date-time field to a value of 11:00 on a particular date, then this means 11 o’clock local time on that date. It won’t matter whether this date is within daylight savings period or not; the value will not change, and should never become an hour out.

If you need to use this field in formulas/automations/reports, you might not get what you expect (see [here](https://the.fibery.io/@public/User_Guide/Guide/Timezones-41)) but the date on the UI will not change (assuming you don’t change your locale).

Note: there would be an issue if there is a change in policy for your locale, e.g. your country decides to stop using daylight savings

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**Author:** ![RonMakesSystems](https://sea2.discourse-cdn.com/flex020/user_avatar/community.fibery.io/ronmakessystems/32/14122_2.png) [@RonMakesSystems](https://community.fibery.io/u/RonMakesSystems)\
**Post date:** [June 11, 2025, 12:17pm UTC](https://community.fibery.io/t/what-happens-with-timezones-and-daylight-savings-time/8961/3 "2025-06-11T12:17:16Z")

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> [@Chr1sG](#):
>
> If you set a date-time field to a value of 11:00 on a particular date, then this means 11 o’clock local time on that date. It won’t matter whether this date is within daylight savings period or not; the value will not change, and should never become an hour out.

Are you sure? From what it says on the guide, the data for the time is stored in UTC, not in “Europe/Amsterdam” or whatever timezone. So when you change from GMT+1 to GMT+2 in daylight savings, the UI will show different time then, no?

So if i schedula a meeting for 9, then daylight saving time kicks in, it will show as 10 the next day? (or the other way around, idk, dst is horrible)

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<div class="post-metadata">

**Author:** ![Chr1sG](https://sea2.discourse-cdn.com/flex020/user_avatar/community.fibery.io/chr1sg/32/3941_2.png) [@Chr1sG](https://community.fibery.io/u/Chr1sG)\
**Post date:** [June 11, 2025, 12:23pm UTC](https://community.fibery.io/t/what-happens-with-timezones-and-daylight-savings-time/8961/4 "2025-06-11T12:23:18Z")

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> [@RonMakesSystems](#):
>
> Are you sure? From what it says on the guide, the data for the time is stored in UTC, not in “Europe/Amsterdam” or whatever timezone.

Imagine you are in western Europe, and you type 1 Jan 2025 11:00 on the UI. This will be stored as 1 Jan 2025 10:00 UTC on the backend, because there is 1 hr difference between UTC and western Europe **on the 1st January**.  
If you type 1 July 2025 11:00 on the UI, it will be stored as 1 July 2025 09:00 UTC, because there is a 2 hr difference **at that time of year**.

> [@RonMakesSystems](#):
>
> when you change from GMT+1 to GMT+2 in daylight savings, the UI will show different time then, no?

No.  
It doesn’t matter what happens over the course of the year (as Europe enters/leaves daylight savings) the statements above remain true.  
Unless the user changes timezone (or Europe abolishes daylight saving) nothing will change this.

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<div class="post-metadata">

**Author:** ![RonMakesSystems](https://sea2.discourse-cdn.com/flex020/user_avatar/community.fibery.io/ronmakessystems/32/14122_2.png) [@RonMakesSystems](https://community.fibery.io/u/RonMakesSystems)\
**Post date:** [June 11, 2025, 12:28pm UTC](https://community.fibery.io/t/what-happens-with-timezones-and-daylight-savings-time/8961/5 "2025-06-11T12:28:49Z")

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> [@Chr1sG](#):
>
> Imagine you are in western Europe, and you type 1 Jan 2025 11:00 on the UI. This will be stored as 1 Jan 2025 10:00 UTC on the backend, because there is 1 hr difference between UTC and western Europe **on the 1st January**.  
> If you type 1 July 2025 11:00 on the UI, it will be stored as 1 July 2025 09:00 UTC, because there is a 2 hr difference **at that time of year**.

This is see, yes.

But if its March 29th, and i set something for march 31st to be at 10:00, then the times change, it will now show on the ui at 11:00, no? Its stored as 9:00 in utc, then my clock moves and now it shows an hour later. Isnt entering or leaving dst effectively just moving timezone? From UTC+1 it becomes UTC+2 or vice versa.

Im confused.

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<div class="post-metadata">

**Author:** ![Chr1sG](https://sea2.discourse-cdn.com/flex020/user_avatar/community.fibery.io/chr1sg/32/3941_2.png) [@Chr1sG](https://community.fibery.io/u/Chr1sG)\
**Post date:** [June 11, 2025, 12:34pm UTC](https://community.fibery.io/t/what-happens-with-timezones-and-daylight-savings-time/8961/6 "2025-06-11T12:34:59Z")

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> [@RonMakesSystems](#):
>
> But if its March 29th, and i set something for march 31st to be at 10:00

If you set something to be 31 Mar 2025 10:00 (on the UI) then it will always show as 31 Mar 2025 10:00 on the UI 😉 (unless you change your timezone)

It doesn’t matter when you set it, today, tomorrow, next year …

(It will be stored as 31 Mar 2025 09:00 UTC internally, but you shouldn’t actually need to care about that. When storing, Fibery doesn’t decide how many hours to subtract based on the current time difference, but **based on the time difference that will apply on 31 Mar 2025** )

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**Author:** ![Michael\_Ichter](https://sea2.discourse-cdn.com/flex020/user_avatar/community.fibery.io/michael_ichter/32/9931_2.png) [@Michael\_Ichter](https://community.fibery.io/u/Michael_Ichter)\
**Post date:** [June 11, 2025, 12:55pm UTC](https://community.fibery.io/t/what-happens-with-timezones-and-daylight-savings-time/8961/7 "2025-06-11T12:55:23Z")

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A thought experiment to explain this. Our team is quite international, and people travel a lot, so I find myself thinking about timezones (and DST) a lot.

I’m in UTC+3. If I set a time for noon, that date value will actually be stored as 9am (since it’s UTC), and in my UI Fibery makes the calculation to noon based off my OS’s locality settings. My colleague living in UTC+2 would see this same date value as 11am, correct?

Now for part two of this thought experiment. Say a due date was set for March 9 at noon in the US, Eastern time zone (this was the first day of DST, UTC-4), so it is stored as 16:00 UTC). For people in Eastern, the date will always appear as March 9th 12:00pm. However, noon of March 8th is actually 23 hours before the due date (since non-DST time is UTC-5). This hour-off discrepancy continues until DST begins at March 9th at 2am, which becomes 3am, which is 9 hours before the due date. So because the due date is in DST, it was stored with daylights savings, i.e. UTC-4, even though we were still in non-DST time (UTC-5).

@ChrisG, let me know if this is correct or not.

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<div class="post-metadata">

**Author:** ![Chr1sG](https://sea2.discourse-cdn.com/flex020/user_avatar/community.fibery.io/chr1sg/32/3941_2.png) [@Chr1sG](https://community.fibery.io/u/Chr1sG)\
**Post date:** [June 11, 2025, 1:26pm UTC](https://community.fibery.io/t/what-happens-with-timezones-and-daylight-savings-time/8961/8 "2025-06-11T13:26:15Z")

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> [@Michael\_Ichter](#):
>
> I’m in UTC+3. If I set a time for noon, that date value will actually be stored as 9am (since it’s UTC), and in my UI Fibery makes the calculation to noon based off my OS’s locality settings. My colleague living in UTC+2 would see this same date value as 11am, correct?

Correct.

> [@Michael\_Ichter](#):
>
> Now for part two of this thought experiment. Say a due date was set for March 9 at noon in the US, Eastern time zone (this was the first day of DST, UTC-4), so it is stored as 16:00 UTC). For people in Eastern, the date will always appear as March 9th 12:00pm.

Sounds right.

> [@Michael\_Ichter](#):
>
> However, noon of March 8th is actually 23 hours before the due date (since non-DST time is UTC-5).

Correct. The time difference between midday on one day and a subsequent day is not always 24hours 🤯

> [@Michael\_Ichter](#):
>
> This hour-off discrepancy continues until DST begins at March 9th at 2am, which becomes 3am, which is 9 hours before the due date.

| Local date time 1 | Local date time 2 | Difference (in hours) |
| --- | --- | --- |
| March 8th 01:59 | March 9th 01:59 | 24 |
| March 8th 02:00 | March 9th 02:00 | Not possible - there is no March 9th 02:xx |
| March 8th 03:00 | March 9th 03:00 | 23 |
| March 8th 12:00 | March 9th 12:00 | 23 |
| March 8th 23:59 | March 9th 23:59 | 23 |
| March 9th 00:00 | March 10th 00:00 | 23 |
| March 9th 01:59 | March 10th 01:59 | 23 |
| March 9th 02:00 | March 10th 02:00 | Not possible - there is no March 9th 02:xx |
| March 9th 03:00 | March 10th 03:00 | 24 |

You can check [here](https://www.timeanddate.com/date/timezoneduration.html).

> [@Michael\_Ichter](#):
>
> So because the due date is in DST, it was stored with daylights savings, i.e. UTC-4, even though we were still in non-DST time (UTC-5).

100% correct 😃

(except I might write it as “_So because the due **date-time** is in DST …_” since the switch to DST happens part way through the date in question)

Ultimately,

> [@Michael\_Ichter](#):
>
> Fibery makes the calculation to noon based off my OS’s locality settings

yes, and it makes the calculation determined by the timezone for your current locality **as it will apply at the date-time being chosen**.
