Export an Outlook calendar to Google and stop keeping two of them

Two calendars is a stable arrangement for about a week. Then a meeting gets booked in the one that was not open, a Saturday commitment exists in only one place, and the habit of checking both wears off at exactly the wrong moment. The search for a way to get Outlook events into Google Calendar is usually the point at which someone decides to stop running two schedules and start running one.

The instructions are short, and the reason people end up with the wrong result anyway is that the two obvious methods produce completely different things. One copies the events as they stand today. The other creates a standing view that keeps updating. Choosing the copy when a connection was wanted is the source of nearly every complaint about calendars drifting apart afterwards.

Decide whether the goal is a copy or a connection

Microsoft is explicit about what the export does. Its own guidance states that exporting an Outlook calendar to Google Calendar is exporting a snapshot of the calendar, and that changes made afterwards in Outlook are not reflected in Google Calendar. The events arrive, they become Google's events, and the two calendars start diverging the moment the next edit happens.

A connection behaves in the opposite way. The events stay owned by Outlook, Google displays them, and every change on the Outlook side shows up without anyone doing anything. The trade is control: a connected calendar is read only in Google, so an event cannot be dragged to a new time from there.

That gives a simple test. If a job or a schedule is ending and the events need to survive in a new home, the copy is correct. If both accounts will keep existing, which is the normal case for a work calendar and a personal one, the connection is correct and the copy is a trap. It is worth deciding this before touching either application, because the work of undoing a bad import is manual and tedious.

The file route, which lives in Outlook on Windows

The documented export path is in Outlook's desktop application on Windows, and Microsoft lists it for Outlook for Microsoft 365, Outlook 2024 and Outlook 2021.

1. Open the Calendar in Outlook and select the calendar to export.
2. Choose File, then Save Calendar.
3. Accept the suggested file name or type one.
4. Open More Options to change what goes into the file.
5. Set the Date Range, choosing a preset or entering custom dates.
6. Set the Detail level.
7. Click OK, then Save.

Two of those steps decide whether the result is usable. The date range defaults to something narrow, and Microsoft warns that choosing a wide range or the whole calendar can produce a large file that takes a while to generate. The detail setting decides how much of each event goes into the file, which matters because an event exported at the lowest level arrives in Google as a block of time with no content, and the only fix is to export again.

The file produced is an iCalendar file, ending in .ics. That is the format Google reads, which is why this route works at all.

Bringing the file into Google Calendar

The receiving half is short, and Microsoft documents it alongside its own steps.

1. Open Google Calendar on a computer.
2. Open Settings from the gear at the top right.
3. On the left, click Import and export.
4. Click Select file from your computer and choose the .ics file.
5. Pick the destination calendar under Add to calendar.
6. Click Import.

The destination choice is the one to slow down for. Importing into the primary calendar mixes a year of work meetings into the calendar that also holds birthdays, and separating them afterwards means editing events one at a time. Creating an empty calendar first and importing into that keeps the work visible, switchable off, and deletable in one action if the import went badly.

Google's own note on importing is worth reading before rather than after: when an event is imported, guests and conference data are not imported. The meetings arrive as appointments with a title, a time and usually a location. Nobody is invited, and no video link travels with them. For an archive that is fine. For a live schedule of meetings other people expect to attend, it is a significant loss, and no amount of care in the export fixes it.

Why these steps do not work on a Mac

Anyone reading the instructions above while sitting at a Mac will not find the Save Calendar command, and the reason is a real difference rather than a missing setting.

Microsoft's documentation for legacy Outlook for Mac describes exporting to an Outlook for Mac Data File, ending in .olm, and states plainly that the only export option available is the .olm archive file. Google Calendar's import accepts .ics and .csv. The two do not meet. An .olm file is a backup that only Outlook can read, so the archive is not a step towards Google Calendar at all. Microsoft also notes that support for legacy Outlook for Mac ends in October 2026, which makes it a poor foundation for a workflow in any case.

That leaves Mac users three practical options. Borrow a Windows machine for the ten minutes the Save Calendar step takes. Sign in to Outlook on the web, publish the calendar, and use the link, which is covered next and is the better answer for most people. Or, where the events only need to be visible rather than owned, connect the two accounts in a desktop calendar that can hold both at once and skip the transfer entirely.

The link route: publish from Outlook, subscribe in Google

This is the route that keeps working after the first day, and it does not depend on which computer is to hand.

On the Outlook side, publishing is in the web interface. Open Calendar settings, go to Calendar, then Shared calendars. Under Publish a calendar, choose the calendar and how much detail to expose, then select Publish. Microsoft's documentation explains the two links that come back. An HTML link opens the calendar in a browser. An ICS link can either be downloaded as a file and imported, or used as a subscription, in which case the subscriber sees the calendar alongside their own and receives updates automatically. Both are read only, and Microsoft notes that how often the ICS calendar syncs depends on the recipient's email provider.

On the Google side, the receiving control is next to "Other calendars", where From URL takes the published address. Google documents that this works only when the other calendar is public, which is precisely what publishing does. The calendar then appears under Other calendars and updates on Google's own schedule.

Two limits in Google's documentation are worth knowing before building anything on this. The subscribe by email address flow is for Google calendars only, stated as not being able to subscribe to calendars that are not from Google, so an Outlook calendar has to arrive as a published address rather than as a person. And subscribing to more than 400 calendars can cause performance problems when browsing calendars, which is only a concern for someone collecting team calendars one at a time.

The same arrangement works in the other direction, and anyone who ends up wanting both views should know it exists. Every Google calendar has a secret address in iCalendar format, found by opening Settings, picking the calendar in the list of calendars that account owns, and clicking Integrate calendar, and Outlook accepts it through Add calendar, then Subscribe from web. Google's own troubleshooting note is that the secret address is the one to use when the public address returns a feed processing error, and that a calendar with no secret address cannot be exported by that person at all. Treat the secret address as a credential rather than a link, because it shows the calendar to anyone holding it without a sign-in, and Google provides a reset for exactly that reason.

One route that sounds simpler than it is: sharing the Outlook calendar directly with a Gmail address. Microsoft states that when an Outlook.com calendar is shared with non-Outlook.com users, such as Gmail users, they can only accept the invitation with an Outlook.com or a Microsoft 365 account. The invitation arrives and cannot be used in Google Calendar, which is a confusing failure unless the limitation is known in advance.

Which route fits which job

Route	Where it runs	Result in Google	Stays current	Fits
Save Calendar, then import	Outlook on Windows	Google's own events, editable	No	A calendar that is being retired
Publish ICS, add From URL	Outlook on the web and Google	A read-only calendar under Other calendars	Yes	Two accounts that both keep going
Publish ICS, download and import	Outlook on the web and Google	Google's own events, editable	No	A one-time copy from a Mac
Sign in to both in one desktop calendar	A Mac calendar application	Both calendars side by side, editable	Yes	Working in one place all day

What no route carries with it

Every method above moves less than the calendar contained, and the gaps are consistent enough to plan around.

Guests and conference data are the largest. Google states they are not imported, so meetings that arrive by file are stripped of both the invitee list and the meeting link. Anyone whose reason for moving calendars is to keep running those meetings needs a connected account rather than a transfer.

Detail level is the second, and it is decided at export time rather than at import time. A calendar saved at the lowest detail level produces events with no descriptions on the other side, and there is no way to recover the text later without exporting again.

Recurring events survive an .ics file in most cases, because the repeat rule is part of the format. They do not reliably survive a spreadsheet. Google documents that repeating events imported from a .csv file might not show as a series and will appear instead as a run of one-time events, which matters for anyone tempted to clean up the data in a spreadsheet on the way through.

Notification settings, categories, colours and permissions do not travel in either direction. Neither does the thing that causes the most trouble in a merged calendar, which is the unbooked time around the events. Two accounts merged into one view immediately reveal double bookings and back to back calls with a commute between them, and a calendar that shows travel time as part of the event is where that gets resolved rather than in the export. What the different applications do and do not hold is laid out in this comparison of Mac calendars.

What to change first

Answer the copy or connection question first, because it determines everything else. If both accounts will still exist next month, publish the Outlook calendar and add it to Google by URL, or sign in to both accounts in one desktop calendar and stop transferring anything. If the Outlook calendar is genuinely being retired, do the Save Calendar export at full detail, import into a new empty Google calendar rather than the primary one, and accept that guests and meeting links will not arrive. A Mac calendar that holds both accounts at once is described in Caltimate.