How to Add Calendar to Outlook

To add a calendar to Outlook, open the Calendar view, click Add calendar in the left sidebar, and pick the source: a built-in holiday calendar, a web ICS URL you subscribe to, a shared mailbox or colleague's calendar, or an .ics file you upload. Which menu you land on depends on whether you run the new Outlook for Windows, Outlook on the web (outlook.com), or classic Outlook. This guide covers all four methods across every version so you can find the exact buttons for your setup.

The steps below were verified against Microsoft's current support documentation in June 2026. Outlook's interface shifts between versions, so each section calls out the differences between new Outlook, Outlook on the web, and classic Outlook.

Add a calendar to Outlook: the four methods at a glance

There are four common things people mean by "add a calendar":

• Add a holiday calendar so national holidays show up automatically.
• Subscribe to a calendar from the web using an ICS URL that keeps refreshing.
• Open a shared mailbox or a colleague's calendar inside your organization.
• Import an .ics file as a one-time snapshot of events.

Every method starts the same way: switch to Calendar (the calendar icon in the left navigation bar) and click Add calendar. From there the options branch out.

How to add holidays to Outlook calendar

Adding national and religious holidays is one of the most common reasons people open the Add calendar menu, so it gets its own section. Each country you add becomes its own calendar layer you can toggle on or off and recolor independently.

New Outlook for Windows

1. Click the Calendar icon in the left sidebar.
2. Click Add calendar at the bottom of the calendar list.
3. Select Holidays (sometimes shown under Interesting calendars).
4. Find the country or region you want and click Add (or toggle it on).
5. Close the dialog. Holidays appear as all-day events and sync to your other Outlook clients.

Outlook on the web (outlook.com)

1. Go to Calendar.
2. In the left pane, click Add calendar.
3. Choose Holidays.
4. Use the search or filter to find a country, then click it to add.

Classic Outlook for Windows

1. Click File > Options > Calendar.
2. Under Calendar options, click Add Holidays.
3. Check the box for each country you want and click OK.

A few gotchas worth knowing: holidays added on the web or in new Outlook sync to mobile automatically, but holidays added the classic way (File > Options) live only in that desktop profile. If you add the same country twice in different versions you can get duplicate entries, so pick one method and stick with it.

If you maintain a custom company holiday schedule, it's often cleaner to publish it as a calendar everyone subscribes to rather than have each person add holidays manually. See how to create a shared calendar in Outlook for that approach.

Subscribe to a calendar from a web (ICS) URL

Subscribing is the right choice when you have a link ending in .ics and you want it to keep updating. Sports schedules, team calendars, conference agendas, and project calendars are usually distributed this way. Unlike a one-time import, a subscribed calendar refreshes on its own whenever the source changes.

New Outlook for Windows

1. Click the Calendar icon, then Add calendar.
2. Select Subscribe from web.
3. Paste the calendar URL (it should end in .ics).
4. Give the calendar a name and pick a color.
5. Click Import (the button labeled Import subscribes you to the live URL).

Outlook on the web

1. Open Calendar > Add calendar.
2. Click Subscribe from web.
3. Paste the ICS link, name the calendar, choose a color and charm, then click Import.

Classic Outlook for Windows

1. Click Add Calendar > From Internet on the Home tab.
2. Paste the iCalendar URL ending in .ics and click OK.
3. Confirm when prompted to subscribe.

Keep your expectations realistic about refresh timing: subscribed ICS calendars don't update in real time. Microsoft controls the polling interval, which can run from a few hours to roughly a day. If a subscribed calendar looks stale, that delay is normal rather than a sync failure. For broader sync problems, see why your Outlook calendar isn't syncing.

Or skip the manual steps: highlight the event text anywhere in your browser, right-click, and the Text to Outlook Calendar extension creates the event for you - dates, times, and locations filled in automatically. It's a faster path than hunting for an ICS link when all you have is plain text like an email or a webpage.

Open a shared mailbox or a colleague's calendar

Inside your organization you can open someone else's calendar directly, as long as they (or an admin) have granted you access. There are two routes: accepting a sharing invitation, or adding the calendar from the directory.

Accept a sharing invitation

When a coworker shares their calendar with you, you get an email. Open it and click Accept - the calendar drops into your People's calendars or Shared calendars group automatically. This is the cleanest path because the permission level the sharer chose travels with the invite.

Add a calendar from the directory (new Outlook and web)

1. Click Add calendar.
2. Select Add from directory (or From directory).
3. Choose your account, then type the person's name or email.
4. Pick them from the results and click Add.

If you only see free/busy blocks and not event details, that's a permission setting on their end, not a bug. The level they granted you controls how much you see. To understand exactly what each level reveals - and how to change it - read our guide to Outlook calendar permissions.

Open a shared mailbox calendar

A shared mailbox (like a team or resource account) behaves a little differently. In new Outlook and the web, use Add calendar > Add from directory and search for the shared mailbox name. In classic Outlook, use Add Calendar > Open Shared Calendar and enter the mailbox name. Admin-level full-access permissions to the mailbox give you the corresponding calendar access.

If you want to go the other direction and let others see your own schedule, walk through how to share your Outlook calendar.

Import an .ics file

Importing is for a one-time load: someone emails you an .ics file with an invite or a batch of events, and you want those events copied into your calendar permanently. Unlike subscribing, an imported file is a frozen snapshot - later changes by the original author won't flow through.

New Outlook for Windows

1. Click the Calendar icon, then Add calendar.
2. Select Upload from file.
3. Click Browse, locate your .ics file, and select it.
4. Choose which calendar to import the events into.
5. Click Import.

Outlook on the web

1. Open Calendar > Add calendar.
2. Choose Upload from file.
3. Browse to the .ics file, pick the destination calendar, and click Import.

Classic Outlook for Windows

1. Click File > Open & Export > Import/Export.
2. Choose Import an iCalendar (.ics) or vCalendar file (.vcs) and click Next.
3. Select the file, then choose Import to merge it into your existing calendar (or Open as New to keep it separate).

Don't have an .ics file yet but need one - say, to send an event to someone or load several events at once? Our free ICS file generator builds a valid .ics from event details in seconds, no Outlook required.

For the reverse situation - turning an email into a calendar entry - see how to create a calendar event from an email in Outlook.

Which method should you use?

Match the method to your goal. Use Holidays for recurring public holidays. Use Subscribe from web when you have an ICS URL and want ongoing updates. Use Add from directory or Accept for live access to a colleague's or shared mailbox calendar. Use Upload from file when you have a static .ics and only need a one-time copy.

And when the calendar you actually want isn't a file or a link at all - just text in an email, a message, or a webpage - skip the import dance entirely. Highlight the text, right-click, and the Text to Outlook Calendar extension reads the date, time, and location and builds the event in one step. It's rated 4 stars and is free for your first five events. You can also grab it from the Outlook extension page.

Frequently Asked Questions

How do I add a calendar to Outlook from a URL?

In new Outlook or Outlook on the web, open Calendar, click Add calendar, then choose Subscribe from web. Paste the URL ending in .ics, give the calendar a name and color, and click Import. The calendar refreshes automatically when the source updates, though the interval is controlled by Microsoft and can take several hours.

What's the difference between subscribing to and importing an .ics file in Outlook?

Subscribing uses a web URL and keeps refreshing, so new and changed events from the source flow into your calendar over time. Importing loads an .ics file once as a snapshot - those events stay in your calendar but never update, even if the original author changes them. Use subscribe for living calendars and import for a one-time copy.

How do I add holidays to my Outlook calendar?

In new Outlook or the web, go to Calendar, click Add calendar, choose Holidays, find your country, and add it. In classic Outlook, go to File > Options > Calendar > Add Holidays and check the countries you want. Each country becomes its own toggleable calendar layer that you can recolor or hide.

Why can't I see details on a calendar shared with me in Outlook?

You're seeing only what the sharer's permission level allows. If they granted Can view when I'm busy, you'll see free/busy blocks but no titles or details. They need to raise your permission to Can view titles and locations or Can view all details for more visibility. This is a permission setting, not a sync error.

How do I open a shared mailbox calendar in Outlook?

In new Outlook and the web, click Add calendar > Add from directory and search for the shared mailbox name. In classic Outlook, use Add Calendar > Open Shared Calendar and type the mailbox name. You need full-access or delegate permission to the mailbox, usually granted by an administrator.