Calendly alternative for Microsoft 365

Does Calendly work with Outlook and Office 365?

Yes, Calendly connects to Office 365 and Outlook.com calendars. Calendly's help center lists Google Calendar, Office 365 or Outlook.com, and Exchange as supported calendar platforms. Calendly Help: Connect your calendar to Calendly, fetched October 8, 2026.

Calendly's Outlook setup page says you can select up to 4 sub-calendars for conflict checks. It says Calendly shows only the first 10 sub-calendars when Microsoft shares more than 10. Calendly Help: How to connect your Office 365 or Outlook.com calendar, updated September 4, 2026, fetched October 8, 2026.

Why does Calendly say approval required with Microsoft?

Calendly shows Approval required when your organization requires a Microsoft admin to approve apps before you use them. Calendly's help page says: “Some organizations use Microsoft security policies that require an admin to approve third-party apps like Calendly.” It also says: “Because this requirement is controlled by Microsoft, Calendly can't bypass it.” The message can appear when you sign up or log in with Microsoft, or when you connect your Outlook calendar.

For people who are not admins, the page says: “Contact your Microsoft admin and ask them to approve Calendly for your organization.” Calendly Help: Approval required when using Microsoft with Calendly, updated August 19, 2026, fetched October 8, 2026.

Can I sign in to OpenCal with Microsoft?

Yes, OpenCal supports sign-in with personal and work Microsoft accounts. OpenCal requests permission to read each calendar event's start time, end time, and free or busy status. It never requests titles, descriptions, locations, or guests. You can connect several Microsoft accounts and several Google accounts to one link.

Microsoft applies the same outside-app rules to OpenCal. If your company requires admin approval, Microsoft requires that approval before OpenCal can read your work calendar. Microsoft's review of OpenCal's publisher verification is pending. Until the review ends, a work account whose company allows consent only for verified publishers cannot connect.

How do I add a Teams calendar that my company does not let OpenCal read?

If your company does not let OpenCal connect to your work calendar, open the Teams or Outlook week view and select Read from screen. You pick the window, and the page reads the busy blocks. The screenshot never leaves your browser. OpenCal stores only the busy times, encrypted. Select Read from screen again when your week changes. The Teams calendar guide shows each step.

Can OpenCal read Outlook on the web?

Yes, with the OpenCal Sync extension for Chrome and Edge. The extension reads Outlook on the web in your signed-in browser. It sends only start and end times to OpenCal. Auto-sync runs every 15 minutes while the browser is open, from an Outlook tab that is already open.

Can bookings go on my Outlook calendar?

Yes, OpenCal can add bookings to an Outlook calendar when you turn this on in Settings, under Booking. By default, OpenCal saves each booking in OpenCal and sends no email. OpenCal then requests permission from Microsoft to write to your calendar. Outlook adds the visitor as a guest and emails the invite. OpenCal does not add a Teams meeting link to the booking.

What does it cost?

OpenCal is free. Calendly's free plan lists “One calendar connection”. Calendly pricing, fetched October 8, 2026.