[ Back to all articles ](https://addcal.co/blog.md) subscription calendars calendar subscription calendar feeds calendar sync What Is a Subscription Calendar and How Do You Subscribe to One? ================================================================ By Tom •August 20, 2026 A subscription calendar is a calendar you follow rather than own. You add it once, by URL, and its events appear alongside your own in Google Calendar, Apple Calendar, Outlook or whichever app you already use. When the publisher changes something, your copy updates itself. You never edit it, you never re-download it, and if you stop caring you unsubscribe and every event disappears in one action. That is the whole concept. Below: how it works, how it differs from a shared calendar or an emailed invite (three things people constantly mix up), how to subscribe in each major app, how quickly changes actually arrive, and how to publish one of your own. How a subscription calendar works --------------------------------- Behind every subscription calendar is a feed: a URL that returns the publisher's events in iCalendar format, the same [.ics format](https://addcal.co/blog/what-is-an-icalendar-ics-file.md) used everywhere else in calendaring. Your calendar app stores the URL and checks it on a schedule. Each time it checks, it mirrors whatever the feed currently says. New events appear, changed events correct themselves, cancelled events vanish. Three properties follow from that design, and they explain nearly everything about how a calendar subscription behaves: - **It is a mirror, not a copy.** The publisher owns the events. You see the current state of their calendar, not a snapshot from the day you subscribed. - **It is read-only.** You cannot drag a subscribed event to a new time, edit its title or delete a single instance. Most apps do let you set your own alerts on it. - **It updates when your app polls, not instantly.** There is no push. How fast a change reaches you depends entirely on which app you use, covered below. Subscribe links often start with `webcal://` rather than `https://`. That prefix is just a signal telling your device "subscribe to this in a calendar app, don't download it". If you want the plumbing, the [webcal explainer](https://addcal.co/blog/what-is-webcal-subscription-calendar-urls.md) covers it properly. Subscription calendar vs shared calendar vs imported file --------------------------------------------------------- These three get conflated all the time, and picking the wrong one is the most common calendar-sharing mistake we see. | | Shared calendar | Subscription calendar | Imported file | | --- | --- | --- | --- | | How people join | Invited one by one, usually by email | Anyone with the link | Open a downloaded .ics file | | Account required | Yes, often on the same platform | No | No | | Works across apps | Poorly (Google to Google, Outlook to Outlook) | Yes, every major app | Yes | | Recipients can edit | Optionally | No | Yes, it is their copy | | Updates after a change | Yes | Yes, on next refresh | Never | | Best for | A small team you work with | An audience of any size | A deliberate frozen copy | Most advice about sharing a calendar with a group tells you to invite each person by email. For a family or a five-person team, fine. Past a dozen people it stops working: you are managing invitations forever, everyone needs the right kind of account, and one wrong permission setting lets a stranger edit your schedule. A subscription calendar flips the model. You publish one link, anyone follows it from any app, and nobody can touch your events. The rule of thumb: **share** with the handful of people you collaborate with, **publish a subscription calendar** for an audience, and **import** only when you specifically want a copy that never changes. How to subscribe to a calendar ------------------------------ You need the feed URL from the publisher. Then, in each app: ### Google Calendar On the web, open Other calendars > the + button > From URL, and paste the link. Google only accepts `http` or `https` here, so if you were given a `webcal://` link, swap the prefix for `https://`. There is no way to do this from the mobile app, but once added on the web it syncs to your phone. Full walkthrough in the [Google Calendar guide](https://addcal.co/blog/how-to-add-an-ics-file-to-google-calendar.md). ### Apple Calendar and iPhone Tapping a `webcal://` link on an iPhone opens a subscribe prompt directly. Otherwise: Settings > Apps > Calendar > Accounts > Add Account > Other > Add Subscribed Calendar, and paste the URL. On a Mac it is File > New Calendar Subscription. Details and screenshots in the [Apple Calendar guide](https://addcal.co/blog/how-to-add-an-ics-file-to-iphone-apple-calendar.md). ### Outlook In Outlook on the web: Add calendar > Subscribe from web, paste the URL, name it. Classic desktop Outlook accepts webcal links directly. The [Outlook guide](https://addcal.co/blog/how-to-add-an-ics-file-to-outlook.md) covers each version's path. How fast do updates arrive? --------------------------- This is the part publishers oversell and subscribers get surprised by. Feeds are polled, and every app polls differently: - **Google Calendar** refreshes external feeds roughly every 24 hours, sometimes faster, sometimes slower, with no setting to change it and no manual refresh button that actually works. - **Apple Calendar** is configurable from every 5 minutes to weekly, per calendar, though iOS treats the interval as a target and defers it on low battery. - **Outlook** typically lands around an hour, honouring refresh hints the publisher can embed in the feed. So a subscription calendar is the right tool for "the venue changed for next month's session" and the wrong tool for "tonight's match is cancelled". If a change is urgent, email people. Design around a worst case of about a day. What people actually subscribe to --------------------------------- Anything that is a schedule rather than a one-off works well as a subscription calendar. The ones we see most: sports fixtures, school term dates, church services, class and course timetables, community events, content creators' release schedules, on-call rotas and market or holiday calendars. If you are looking for calendars to subscribe to, start with the organisations you already follow. Many clubs, schools and venues publish a feed and label it "add to calendar" or "subscribe". Publishing your own subscription calendar ----------------------------------------- There are two routes. **Host a feed yourself.** Any HTTPS endpoint that serves valid iCalendar data is a subscription calendar. If you can generate a file and keep it updated on a server, that works, and the [webcal explainer](https://addcal.co/blog/what-is-webcal-subscription-calendar-urls.md) includes the exact headers and properties a well-behaved feed should emit. The catch is everything around the feed: keeping event identifiers stable so subscribers don't get duplicate notifications, handling timezones, and knowing anything about who subscribed, which a raw feed cannot tell you. **Use a service.** With [AddCal's subscription calendars](https://addcal.co/solutions/subscription-calendars.md), you create a calendar, add events, and share one subscribe link that works in Google, Apple, Outlook, Office 365 and Yahoo. Edit an event and every subscriber's calendar picks up the change on their next refresh, without you re-sending anything. You also get the things a bare feed can't do: see and export who subscribed, collect names and emails on subscribe if you want them, revoke an individual subscriber's access, and brand the calendar page as your own. When a subscription calendar is the wrong tool ---------------------------------------------- Subscriptions are for ongoing schedules. Reach for something else when: - **It is one event.** Asking someone to follow an entire calendar for a single webinar is friction they will not tolerate. Use an [add to calendar link](https://addcal.co/solutions/add-to-calendar-links.md) instead: one click puts that event in whichever app the recipient uses, as their own editable copy. - **You need to know who is coming.** A feed has no RSVP. Attendance needs a link with registration behind it. - **Changes are time-critical.** The polling delay above applies to every subscriber, every time. Subscribe for schedules, link for individual events. That one split resolves most calendar-sharing decisions. If you publish events on any kind of recurring basis, [set up a subscription calendar](https://addcal.co/solutions/subscription-calendars.md) and send one link. It takes under a minute, and it is the last time you will need to send anything. Last updated on August 20, 2026 ![Tom](https://cdn.addcal.co/static/authors/atymic.jpg)### Tom Founder Built Calndr.link in 2020 because an event link broke in Outlook and it annoyed him enough to fix it properly. Six years later he can tell you exactly how each calendar app mangles a timezone, which is a worse party trick than it sounds. Otherwise found hanging off a rock somewhere in Australia. [GitHub](https://github.com/atymic)[X](https://x.com/atymic) ### Related articles [What Is webcal? Subscription Calendar URLs Explained The webcal scheme tells a device to subscribe to a calendar rather than download it. It is not a protocol and it was never standardised, but it is universally supported. How it works, refresh intervals per client, how to build a feed, and why the URL is the credential.](https://addcal.co/blog/what-is-webcal-subscription-calendar-urls.md)[How to Sync Your Blackbaud Calendar With Google, Outlook, and Apple Calendar Blackbaud Education Management powers calendars at thousands of private schools, but syncing those calendars to Google, Outlook, or Apple Calendar is a mess. Here's why it breaks and how to fix it with AddCal.](https://addcal.co/blog/how-to-sync-your-blackbaud-calendar-with-google-outlook-and-apple-calendar.md)[Calndr.link Is Now AddCal: What Changed, What Still Works Calndr.link became AddCal in 2025. Every old link and API integration still works. Here is where Calndr.link came from, what changed in the rebuild, and what to do about events you created on the old system.](https://addcal.co/blog/calndr-link-is-now-addcal.md) [ Browse all articles ](https://addcal.co/blog.md)