GUIDE

Combine Google and Outlook calendars without admin approval

Q: What if my Google admin disabled the secret iCal address?

Use Tab Sync instead. Open Google Calendar in a browser tab as you normally would and sync the tab; the calendar follows it from then on. No feed URL, no API access, and no admin setting is involved.

Q: Both my accounts are personal. Is this overkill?

If neither account is managed, you can also cross-subscribe natively for free: publish an ICS feed from Outlook and subscribe in Google, or use Google's secret address in Outlook. A combined local view is still useful for color coding, conflict detection, and one place to look, but you have more options when no admin is in the way.

Updated: July 3, 2026 · 5 min read

The two-IT-departments problem

You have a Google calendar on one side, an Outlook calendar on the other, and at least one of them belongs to an organization that locks things down. Maybe it is a Google Workspace client and a Microsoft 365 client. Maybe it is your own Gmail plus a managed work account. Either way, you want one view, and this guide covers how to combine Google and Outlook calendars without admin approval, including the case where both sides are locked.

Cross-provider is the hardest combination for a reason. Merging two Outlook accounts or two Google accounts has native paths inside each ecosystem. Google-to-Outlook needs a bridge, and every classic bridge needs permission from at least one side. Since November 2025, Microsoft Entra's default settings block user consent to apps requesting calendar permissions, so the Microsoft side usually needs an admin. Google Workspace admins can disable external sharing and the secret iCal address, so the Google side often needs one too. When both accounts are managed, you need two IT departments to say yes before a conventional sync tool can even start.

The routes that need someone's approval

Worth knowing, because when they are available they are good:

OAuth sync services. CalendarBridge (4, 8, or 32 dollars per user per month, with patented server-mediated two-way sync, booking pages, and a HIPAA BAA), OneCal, Reclaim.ai, and Morgen genuinely sync events between accounts, both directions. Each account has to be connected through OAuth, and all four vendors publish admin-approval help articles for managed Microsoft tenants, because that connection is now blocked by default. One locked side breaks the whole bridge. If you hit the wall, here is what that screen means and what to do about it.
Native ICS cross-subscription. Publish a feed from Outlook and subscribe in Google, or paste Google's secret iCal address into Outlook. Free and built in, but each admin can switch it off, and refresh lag between providers can run to hours. If the secret address option has vanished from your Google settings, that was an admin: Google Calendar secret address missing.

The route that needs no one: combine them locally

manyCalendars skips the bridge entirely. Instead of syncing events between the two accounts, it overlays both calendars in one view inside your desktop browser, on your machine. There is no account to create, no OAuth flow, and no API request, so there is nothing for either IT department to approve or block. It is the only calendar tool we know of that works when IT says no. Whatever mix of locked and open you are dealing with, there is a way in:

Install the extension. Every install starts a 14-day full trial, no card and no account. Get it here.
Add anything that still has a working feed. .ics files and feed URLs are unlimited on the free tier, 100 percent local.
Tab Sync the locked accounts. Open the Google or Outlook calendar in a browser tab, the same tab you check ten times a day anyway, and sync it. From then on that calendar follows its tab.
Make it readable. Color-code per client and flip between month, week, and day views. Premium adds cross-calendar conflict detection and one-click availability sharing across both providers.

Tab Sync is part of Pro at 15 dollars a month or 150 dollars a year; conflict detection and availability sharing are Premium at 29 dollars a month or 290 dollars a year. The free tier handles unlimited feed-based calendars forever. Full details on the pricing page.

The honest limits

manyCalendars is a desktop browser extension only; there is no phone app. Tab Sync reads what is visible in a tab you are signed into, and it is read-only on the source: it will not create an event in Google because you added one in Outlook, or the reverse. If you need true two-way sync and both organizations will approve an OAuth connection, a cloud service is the right tool and CalendarBridge is a good one. If approval is not coming, a combined local view solves the problem that actually costs you money: not seeing both schedules at once and double-booking a client.

Common questions

Do I need to connect my Google or Microsoft account?

No. manyCalendars never asks you to sign in, never runs an OAuth flow, and does not even have accounts. That is exactly why there is nothing for an admin to approve.

What if my Google admin disabled the secret iCal address?

Use Tab Sync instead. Open Google Calendar in a tab as you normally would and sync it; the calendar follows the tab from then on. No feed URL and no admin setting involved.

Both my accounts are personal. Is this overkill?

If neither account is managed, native cross-subscription works and costs nothing, so try that first. A combined local view still earns its keep with color coding, conflict detection, and one place to look, but you have more options when no admin is in the way.