How to change timezone AND KEEP the local times of your appointments?

Welcome Hao,

Thank you for reaching out to Microsoft Q&A forum.  

I understand you are trying to change the calendar time zone while keeping the same local start and end times for your existing appointments. 

Regarding your case, I can see that QA Assist has already provided some helpful troubleshooting steps. Besides, you may find these additional options helpful:  

Step 1: Create a temporary duplicate calendar to preserve the original local times 

• Open Calendar in Outlook on the web 
• Right‑click the calendar and choose Add calendar 
• Create a blank calendar and name it temporarily 

Step 2: Copy or move the affected appointments to the temporary calendar 

• Select the appointments in the original calendar 
• Copy or move them into the temporary calendar before changing the time zone 

Step 3: Change the primary calendar time zone 

• Select the Settings gear icon 
• Go to Calendar and then View 
• Change the Display my calendar in time zone setting to the correct time zone and save 

Step 4: Move the appointments back to the original calendar 

• Edit each appointment after moving it back to confirm the intended local time 
• Adjust only if needed to match the original schedule 

Step 5: Keep an additional time zone enabled for reference 

• Go to Calendar and then View 
• Add another time zone and enable Show in calendar 

Step 6: Remove the temporary calendar once all appointments are verified 

Note: You may notice that two of the steps are similar to those mentioned previously; however, the overall guidance is intentionally structured to provide a completer and more reliable workaround. Please follow all steps to ensure the best possible outcome. 

I hope this information helps resolve your issue. If you have any further questions, please don’t hesitate to contact me again in this thread. 

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In Outlook on the web and Outlook.com, changing the calendar time zone always shifts existing items to keep their absolute time the same, so there is no built‑in way to change the time zone and also keep the displayed local times of existing appointments unchanged.

To approximate “keep local times” when switching time zones, appointments must be adjusted manually (or recreated) after changing the time zone:

1. Change the calendar time zone:
   1. Select Settings (gear icon).
   2. Select Calendar > View.
   3. Under Time zones, choose Display my calendar in time zone and select the new time zone.
   4. Select Save.
2. Manually correct affected appointments by editing each one and resetting the start/end times to the desired local time in the new time zone.

Additional time zones can be displayed for reference, but they do not change how items are stored or prevent the time shift when changing the primary time zone:

1. Select Settings > Calendar > View.
2. Select Add time zone.
3. Choose a city under Other time zones, optionally add a Label, select Show in calendar, and Save.

This only helps compare time zones; it does not preserve local times when switching the primary time zone.

References:

• Manage time zone settings in Outlook