Proton Calendar vs Google Calendar

Why Consider Proton Calendar over Google Calendar?

Google Calendar is convenient. It is also one of the most behaviourally revealing datasets you can hand to an advertising company. Every meeting, every commute, every recurring “therapy” or “interview” event is logged against your identity by Google LLC, a US corporation operating under the CLOUD Act and FISA Section 702. Google states calendar data is not used for ads — but it is used across Google’s product surface, and it is reachable by US legal process.

Proton Calendar is built by Proton AG in Geneva, Switzerland, by the same team responsible for Proton Mail, Proton Drive, Proton VPN, and Proton Pass. It is end-to-end encrypted, open-source on the client side, and governed by Swiss law — historically one of the strongest privacy jurisdictions in the world.

Feature Comparison

Feature	Proton Calendar	Google Calendar
End-to-end encryption	Yes — events, locations, attendees	No
Open-source clients	Yes (web, iOS, Android)	No
Jurisdiction	Switzerland	United States
GDPR compliant	Full (Swiss/EU framework)	Partial (US entity)
iCal import/export	Yes	Yes
CalDAV sync	Yes (paid plans)	Yes
Shared calendars	Yes (E2E between Proton users)	Yes
Meeting scheduling	Basic	Advanced (Appointments, Slots)
Native Meet integration	Via Proton ecosystem	Yes (Google Meet)
Room / resource booking	Limited	Workspace Enterprise
Free tier	Yes	Yes

Pricing

• Proton Free — Includes Proton Calendar, Proton Mail (1 GB), Proton VPN free tier
• Proton Mail Plus — €3.99/month (annual) — 15 GB, 10 calendars, full features
• Proton Unlimited — €9.99/month — 500 GB, all Proton services
• Proton Business — From €6.99/user/month — domain, admin, larger storage
• Google Calendar — Free with Google account
• Google Workspace Business Starter — $6/user/month — includes Calendar with admin

Proton’s paid bundles include calendar, mail, drive, VPN, and password manager in a way Google does not match outside Workspace Enterprise.

Privacy and Data Sovereignty

• Headquartered in Geneva, Switzerland — outside CLOUD Act and FISA 702
• Swiss data protection law, with adequacy under GDPR for EU residents
• End-to-end encryption with keys derived from your Proton password
• Proton cannot read your event content even if compelled
• Open-source clients allow independent audit of the encryption
• Funded by paid subscriptions, not advertising — no behavioural profiling
• Independent foundation ownership (Proton Foundation, established 2024)

Calendar metadata is some of the most sensitive data you produce. Proton’s architecture is designed so that you and only you can read it.

Migration Considerations

Estimated time: 30–60 minutes. Difficulty: Easy.

1. Create or sign in to a Proton account. Proton Free includes Calendar.
2. Export from Google Calendar. Visit Google Takeout, select Calendar only, and download the resulting .ics files (one per calendar).
3. Import into Proton Calendar. Settings → Calendars → Import. Drag in each .ics file. Events, recurrences, and reminders come across.
4. Set up sharing. Re-invite collaborators to your Proton calendar. For non-Proton attendees, use the public iCal URL — they will see events without end-to-end encryption, but the data still leaves Proton encrypted in transit.
5. Connect Apple Calendar / Thunderbird / Outlook via CalDAV if you want a native client. Settings → Calendars → CalDAV gives you the credentials.
6. Wind down Google Calendar. Forward outstanding invites, remove yourself from old shared calendars, and stop accepting new invitations to your Gmail address. Consider also migrating your mail with Proton’s Easy Switch tool.

The Bottom Line

Google Calendar is a brilliant product whose business model depends on owning your behaviour. Proton Calendar gives up some of the deepest integration features and asks you to pay if you want more than the generous free tier — but in exchange, your meetings, locations, and attendee lists become things only you can read.

For European individuals and businesses moving away from US-hosted productivity stacks, Proton Calendar is the obvious next step after Proton Mail — and the combination forms a credible, encrypted, Swiss-jurisdiction alternative to Google’s calendar-and-mail flywheel.

Frequently Asked Questions

How is Proton Calendar end-to-end encrypted?

Event titles, descriptions, locations, notes, and attendee lists are encrypted on your device with keys derived from your Proton account. Only timestamps and basic event metadata needed for sync are visible to Proton. Even a court order to Proton produces ciphertext, not your calendar.

What does Google actually do with my calendar data?

Google Calendar data is processed by Google LLC in the US. Google states it is not used to personalise ads, but it is used for cross-product features (Google Now, Assistant, location reminders) and is subject to US legal process. Calendar data is some of the richest behavioural signal Google holds — who you meet, when, where, and how often.

Does Proton Calendar work with Outlook or Apple Calendar?

Yes, via CalDAV. CalDAV access is available on Proton paid plans and allows native sync from Apple Calendar, Thunderbird, and other CalDAV-compatible clients. Outlook requires a third-party CalDAV connector. The Proton-native apps for iOS, Android, and web remain the smoothest experience.

Can I share a Proton calendar with a non-Proton user?

Yes. You can share a calendar as a public link or via iCal subscription URL with anyone. Sharing with another Proton user keeps end-to-end encryption intact; sharing with non-Proton users falls back to standard iCal — still encrypted in transit but not end-to-end.

How do I migrate from Google Calendar?

Use Google Takeout to export your calendars as iCal (.ics) files, then import each calendar into Proton Calendar through Settings → Import. Recurring events, exceptions, and most attachments come across cleanly. Set up calendar redirection in Gmail or use Proton's Easy Switch tool to also migrate email and contacts.