Sharing an Outlook calendar in one paragraph
To share your Outlook calendar, open Calendar in the navigation pane, choose Home > Share calendar, pick the calendar and the person, set their permission level, and select Share. That path is the one Microsoft documents. The rest of this page covers the three things it leaves open: what each permission level actually reveals to the recipient, the organization-wide sharing default you never set yourself, and how to lock a calendar back down once access has travelled further than you meant.
How do you share your Outlook calendar with someone?
To share your Outlook calendar with a named person, open Outlook, select Calendar in the navigation pane, then go to Home > Share calendar. Pick which calendar you are sharing, then type the person's name or email address, choose a level from the dropdown beside their entry, and select Share. That is the sequence Microsoft documents for Outlook and Microsoft 365.
Two details decide what actually happens next. The recipient gets an invitation, and the calendar does not appear on their side until they accept it, so a share that looks complete on your screen can still be sitting unopened in someone's inbox. And the level dropdown is set per person, not per calendar: two colleagues added to the same calendar can hold two different levels.
What each dropdown option exposes is the next section. Editing rights and delegate access run through a separate Microsoft article and are not enumerated here.
What does each Outlook sharing permission level actually reveal?
Outlook calendar visibility settings offer three view levels, and each one adds a fixed block of fields on top of the one below it.
Can view when I'm busy shows time blocks only. The recipient sees that something occupies Thursday 2pm to 3pm, and nothing about what it is.
Can view titles and locations adds two fields: the event subject and the location string. "Dentist appointment" and the clinic's address both become readable.
Can view all details adds the rest of what the event carries — the body text, any attachments, and the attendee list.
The jump between rungs is where people get caught. There is no option that shows titles but withholds locations; the two arrive together. There is nothing between the middle and top rungs either, so the moment you want someone to read a description, you have also given them every attendee and every attachment on every event in that calendar.
The dropdown offers exactly these three rungs, and each is a fixed bundle of fields rather than a set of switches you can mix.
Why can colleagues already see my Outlook calendar?
Your Microsoft 365 tenant carries an organisation-wide sharing default, and it grants everyone inside the tenant a baseline view of every other calendar — most commonly free/busy. Nobody in your address book had to request access, and you never approved it. It is a property of the tenant, configured by whoever administers it.
That default is why Outlook calendar privacy settings can look empty while colleagues still see your week. The organisation-level policy does not appear in the per-person share list on your Calendar tab; that list shows only the entries you added yourself. So your per-person sharing is additive — every level you grant sits on top of a floor you cannot see or edit from your own calendar.
Two consequences. Raising the tenant default, or lowering it, is an administrator action; ask whoever runs your tenant rather than hunting for the control in your own settings. What you can change alone is per-event: marking individual events private, which the next section covers.
How do you make your Outlook calendar private?
To make your Outlook calendar private, open Calendar, go to Home > Share calendar, and lower each person's dropdown to "Can view when I'm busy" — or remove their entry outright, which withdraws the share. Those per-person dropdowns are the whole-calendar half of Outlook calendar privacy settings; what each rung exposes is covered in the permission levels section above.
For a single event, open it and mark it Private. The title, location and body stop being readable to anyone holding a view permission on that calendar, while the time block still shows as busy.
Private hides the event's detail; the busy block stays visible, so someone with a view permission still sees that the slot is taken. It is set per event at the moment you set it, so marking new events private does nothing to the events already sitting in your calendar; those have to be opened and marked one by one. And a delegate with full access to your mailbox may still be able to read items you marked Private, depending on how that delegate was configured — Microsoft documents delegate settings in its own separate article.
What if you need something between Outlook's permission levels?
A Keeper.sh iCal feed splits those fields into independent switches instead of fixed bundles. Include Event Name, Include Event Description and Include Event Location are three separate toggles, each off by default, so a contractor can receive event names with no locations attached — the combination Outlook's middle rung will not give you. With every toggle off, each event in the feed carries the title "Busy" and nothing else.
Event Filters leave whole categories out of a link: Exclude All Day Events, Exclude Focus Time, Exclude Out of Office. The out-of-office filter matches Outlook's own out-of-office events, so a client can see everything except the blocks you set aside.
Feeds are named, and each one carries its own calendar selection and its own settings, so different audiences get different links with different disclosure. Rida F'kih, who maintains Keeper.sh, describes his own: "I share my calendar with my girlfriend, privatized, with filters applied."
Choosing which calendars a feed carries is free. The toggles and extra feeds are Pro, $5 per month.
How quickly does a shared Outlook calendar update for the other person?
A calendar you shared inside Outlook to another Outlook user updates through Microsoft's own sync, so what the recipient sees is effectively current. A calendar added with Add calendar > Subscribe from web is a subscription, and Microsoft documents those updates as happening approximately every 6 hours, noting that the update can take more than 24 hours.
The same honesty applies to a Keeper.sh iCal feed. Keeper.sh rebuilds the file on every read, so the link never serves a stale cached copy — but it is still a subscription, and it inherits whatever polling schedule the recipient's app keeps. Keeper.sh cannot make an app ask sooner.
A Keeper.sh connection is the separate mechanism. It writes real events into the destination calendar, which then syncs natively through Google or Microsoft themselves. On Free, those writes land within 30 minutes; on Pro with Google or Outlook, they land within seconds via provider push. Those numbers belong to connections. A feed link never inherits them, whichever plan you are on.
How do you stop sharing an Outlook calendar you already shared?
To revoke a share you already sent, open Calendar, go to Home > Share calendar, find the person in the list, and remove their entry. Their copy stops updating.
A link works differently. A published or subscribed calendar address carries no person-level grant — anyone holding it keeps what it serves until the address itself changes, and forwarding costs nothing.
Keeper.sh has the same shape, with one gap worth naming. A non-default feed can be deleted, and calendar apps subscribed to its link stop receiving events. The default feed cannot be deleted, and there is no token rotation. Free includes one feed, and it is the default. So a Free user whose single link leaks has one lever: empty that feed's calendar selection, which is not plan-gated and leaves the link serving an empty calendar. Upgrading to Pro does not retire the leaked address — the default feed still cannot be deleted or rotated — but it lets you create a second, narrower feed to hand out instead.