Bookings with me vs Microsoft Bookings vs IntoCal: which Outlook scheduler checks shared calendars?

Short answer: Bookings with me only checks your own Outlook calendar. It cannot look at a colleague's calendar, a shared mailbox or a team calendar before offering a time. Microsoft Bookings checks the free/busy of every staff member you add to a booking calendar, but only inside your Microsoft 365 tenant. IntoCal checks the connected Outlook and Google calendars of every team member on a team event, then offers only the times that actually work.

Why "shared calendar" means three different things

When people say a scheduler should "check the shared calendar", they usually mean one of these:

1. A colleague's calendar. You want a client to book you only when your co-host is also free.
2. A pool of people. Any of three advisers can take the call, whoever is free.
3. A shared mailbox or room calendar. A resource such as "Meeting Room 2" or "sales@" that several people write to.

The three tools handle these cases very differently, so test the case you actually have before you pick one.

Bookings with me: your calendar only

Bookings with me is the personal page in Outlook on the web. It reads your own default calendar and hides any slot where you are marked busy. That is all it reads. If your manager has to join, or you keep client work in a separate shared calendar, those events are invisible to the page and guests can book straight over them.

It is a good fit if you work alone, live in one Outlook calendar, and only need a link. It does not fit any of the three "shared" cases above.

Microsoft Bookings: staff inside your tenant

Microsoft Bookings creates a booking calendar (technically a special mailbox) and lets you add staff. For each service you choose which staff can deliver it, and Bookings checks those people's Outlook free/busy before offering a slot. That covers cases 1 and 2 well, as long as everyone is in the same Microsoft 365 tenant.

Where it gets awkward:

• People outside the tenant (a contractor on Google Workspace, a partner company) can be added as staff, but their real calendar is not checked.
• Room and shared mailbox calendars are not checked as a booking condition unless you treat them as a staff member, which most admins avoid.
• Admin settings decide a lot. If your tenant blocks free/busy sharing, Bookings can quietly show times a person is busy.
• Licensing. Every person who uses it needs an eligible Microsoft 365 plan.

We cover the rest in Microsoft Bookings limitations.

IntoCal: every member's connected calendars, Outlook or Google

In IntoCal each team member connects their own calendar, Outlook or Google, from Dashboard → Integrations. When a guest opens a team event, IntoCal reads the busy times from every connected calendar of every member on that event, removes existing IntoCal bookings, and only then shows slots. You choose how the team is used:

• Collective: a slot appears only when all chosen members are free. This is case 1, the co-host meeting.
• Round-robin: a slot appears when any member is free, and the booking goes to the next person in line. This is case 2.
• Let the guest choose: the guest picks a person, then sees that person's real availability.

The difference from Microsoft Bookings is that the members do not have to share a tenant, or even use Outlook. A Google Workspace contractor and an M365 employee can sit on the same round-robin. For a plain explanation of the three modes, read round-robin, collective and host-picker explained.

One honest limit: IntoCal checks the calendars a member connects. If a team relies on a shared mailbox or room calendar that no person has connected, that calendar is not checked. The usual fix is to have the person who owns that resource connect it as their calendar.

Side-by-side

How to set up a team event in IntoCal that checks everyone

1. Create a free account at intocal.com/signup and connect your Outlook calendar in Dashboard → Integrations.
2. Open Dashboard → Team and invite your colleagues by email.
3. Ask each colleague to sign in and connect their own Outlook or Google calendar. This step is what makes their busy time count.
4. Create an event type, choose Collective or Round-robin, and add the members.
5. Open the booking link in a private browser window and check it against a time you know a colleague is busy. That slot should be missing.

New bookings are written back to each assigned person's calendar with a Teams or IntoCal Meet link, so nobody has to copy anything across. If a slot still shows when someone is busy, the cause is usually the event's "Show as" status; this guide explains the fix.

Which one should you use?

• Solo, Outlook only, link is enough: Bookings with me is fine and already paid for.
• Whole team in one M365 tenant, no public website embed needed: Microsoft Bookings works.
• Mixed Outlook and Google, outside partners, a website embed, or AI assistants booking for you: IntoCal.

For the wider comparison of the two Microsoft products on their own, see Outlook booking page vs Microsoft Bookings.