On Sunday 1 November 2026, most of North America set its clocks back an hour. Alberta did not. The province now stays on Alberta Time all year: six hours behind Coordinated Universal Time (UTC-6), which is what summer time used to be.
Most phones and laptops took it in their stride. Calendars are another story. If your 9 am meeting turned up at 10 am this week, your computer is not broken. It is following instructions written before the rules changed, and Outlook will not rewrite them for you. Microsoft puts it plainly: “Existing calendar events do not migrate automatically.”
What changed, and who moved
Alberta’s last clock change was the spring forward on 8 March 2026. In a 2021 referendum, 50.2 per cent of Albertans voted to keep changing their clocks; this year the province made daylight time permanent anyway, and says it will gather feedback after the first full year. British Columbia (UTC-7) and Manitoba (UTC-5) made the same move on the same day. Saskatchewan never changed its clocks. Ontario, Quebec, the Atlantic provinces and most of the United States still do.
So Alberta’s clocks now stand still, but the gap to some of the places it works with does not:
| How far each city is from Calgary | Summer | Last winter | This winter |
|---|---|---|---|
| Vancouver | 1 hour behind | 1 hour behind | 1 hour behind |
| Regina | Same time | 1 hour ahead | Same time |
| Winnipeg | 1 hour ahead | 1 hour ahead | 1 hour ahead |
| Toronto | 2 hours ahead | 2 hours ahead | 1 hour ahead |
| Denver | Same time | Same time | 1 hour behind |
| London, UK | 7 hours ahead | 7 hours ahead | 6 hours ahead |
Why a meeting moves on its own
Outlook does not store “9 am”. It stores a single moment, worked out using the rules of the time zone the meeting was booked in. A December meeting booked in September under the old Mountain Time rules was saved on the assumption that Alberta would fall back to UTC-7. That moment now arrives at 10 am Alberta time.
There are two kinds of moved meeting, and only one is a fault:
- Booked in Alberta under the old rules. These show an hour late for everyone in Alberta, and they need fixing.
- Booked by someone in Toronto, the United States or anywhere else that still changes clocks. If the stand-up with head office moved from 9 am to 10 am Calgary time, Outlook is right: the gap changed. Leave it, or agree a new time with the organiser.
One clock, many names
Before touching any setting, it helps to know what “right” looks like, because hardly anything calls the new time by the same name:
- The Government of Alberta calls it Alberta Time (ABT).
- Windows and Outlook call it (UTC-06:00) Mountain Time (Alberta). Inside Windows, its ID is “Alberta Standard Time”.
- The international time zone database used by phones, Macs and most servers records it with the abbreviation CST, like Saskatchewan, so some systems will label Calgary meetings that way.
- Where software has not caught up, Microsoft’s stopgap advice for Alberta is to pick the Saskatchewan time zone. For some automations in Manitoba, its temporary answer is the time zone for Bogota, Colombia.
None of these is a fault. The setting to watch for is the old (UTC-07:00) Mountain Time (US & Canada), which still falls back every November.
The fix, in five steps
- Check the computer’s time zone, not just the clock. In Windows, open Settings, then Time & language, then Date & time. It should say (UTC-06:00) Mountain Time (Alberta). If that option is missing, the PC is missing the September or October 2026 Windows update, and Microsoft says devices on unsupported Windows versions will not receive it at all. Do not fix the time by changing the clock by hand. The clock is not wrong, the time zone is, and a computer set an hour out falls out of step with the services it signs in to: on a company network, Windows sign-in tolerates five minutes of difference by default.
- Set Outlook’s calendar time zone. In classic Outlook: File, Options, Calendar, Time zones. In new Outlook and Outlook on the web: Settings, Calendar, View, then “Display my calendar in time zone”. On a Mac, Outlook needs build 16.114.26102345 or later to offer the new zone.
- Fix the meetings you organised. Only the organiser can. Open the meeting (for a recurring one, choose Edit series), select the time zone button, choose Mountain Time (Alberta) and send the update. Microsoft’s steps cover each version of Outlook.
- Write down any one-off changes first. Microsoft warns that changing a series’ time zone resets any single occurrence that had been moved. Move those again afterwards.
- Warn attendees outside Alberta. Fixing a meeting moves it for them. A 9 am Calgary meeting that Toronto colleagues saw at 11 am will now show at 10 am Toronto time, and one line in the update saves a no-show.
On phones, Outlook for iPhone and Android uses the phone’s own time zone for new events, and existing events have to be fixed on a computer or in Outlook on the web. The province’s advice for the phone itself is to install the latest updates and leave automatic date, time and time zone switched on.
Problems still open
- Mac and iPhone showing Alberta meetings an hour late. Since October, organisations have reported that new Outlook for Mac and Outlook for iPhone show some Alberta meetings an hour late while Outlook on the web shows the right time. Microsoft has not confirmed a cause or a fix. Check a meeting in Outlook on the web before “correcting” it, or you may break one that was fine.
- No bulk fix yet. Microsoft is building an Exchange Online tool that lets administrators fix one-off meetings across a whole organisation. Its target date has already slipped from 28 October to 4 November, and there is no date for recurring meetings, so those need fixing by hand.
- Free/busy and work hours. Microsoft is still investigating how free/busy information and the Work Hours and Location feature behave in new Outlook and Outlook on the web.
Beyond Outlook: everything else with a clock
Calendars are the visible part. Microsoft’s product guidance lists more, and most businesses have a few of these:
- Meeting room screens. Teams Rooms on Windows showed the time an hour behind Windows until Edge and WebView2 were updated.
- Phone menus. Teams auto attendants may need their time zones set by hand. On any phone system, check that business hours, after-hours greetings and holiday schedules switch at the right time. A system still on the old rules tells 9:30 am callers that you are closed.
- Automations. Power Automate flows and Azure Automation schedules on US-linked time zones drift by an hour. Microsoft’s interim advice is the Saskatchewan time zone for Alberta, and not to use the new IDs yet.
- Booking pages. Microsoft Bookings now offers the new time zones for new bookings, so check that your booking page uses one.
- Everything with a schedule: time clocks, door access, security cameras, backups and maintenance windows. Most update themselves; older or unsupported devices may need setting by hand.
Put 14 March 2027 in your calendar
It happens again in spring, in reverse. On 14 March 2027, Ontario, Quebec and most of the United States spring forward while Alberta stays put. Toronto goes back to two hours ahead, Denver back to the same time, and meetings booked by people in those places will move by an hour for Calgary again. That is the pattern from now on: twice a year, Alberta stands still and its neighbours move around it.
Two habits help:
- Put both times in invitations to people outside Alberta for the first few weeks after each change, such as “10:00 Calgary / 11:00 Toronto”.
- Book new recurring meetings only once Outlook is on Mountain Time (Alberta), so you never have to fix them twice.
Keeping on top of it
Changes like this land on busy people who have better things to do than read Microsoft support pages. Keeping every PC on current Windows updates is part of our managed service desk, and our Microsoft 365 service looks after the tenant settings behind Outlook, Teams and Bookings. If your phone menu has the hours wrong, our business VoIP service covers after-hours and holiday routing.
This article reflects Microsoft’s guidance as updated on 2 November 2026. Microsoft is still releasing fixes, so check its Canada time zone guidance for later changes.