Moving From Proton Mail to Gmail or Google Workspace

Moving from Proton Mail to Gmail or Google Workspace is the migration most guides skip — most go the other way. If you have landed here, the reason is usually pragmatic: shared calendars, Docs, Meet, Workspace admin, a team that lives in Google, or a client who insists on it. The mail is the smallest part of that decision and the hardest part of the switch.

It is harder because Proton was designed so mail cannot leave easily. End-to-end encryption on Proton-to-Proton and PGP mail, zero-access encryption on everything else, and no plain-IMAP endpoint — that is why the export needs a specific tool rather than an OAuth click. This guide covers what moves, the pre-migration checklist, the two supported export paths, how to load into Gmail or Workspace, what breaks, and how to keep receiving mail during the switch.

We build AI Emaily, and there is one restrained placement near the end. Everything above it is the migration.

What actually moves — and what doesn't#

Two things determine what you can carry across. First: Proton stores mail encrypted, and only Proton's own apps can decrypt it. Second: encryption that was end-to-end between two Proton users, or PGP-signed between Proton and an outside sender, cannot follow the message into a mailbox that does not hold the key. Once decrypted and uploaded to Gmail, a message sits on Google's servers under Google's encryption model — not equivalent, and pretending otherwise is the one thing this migration cannot honestly do.

The pre-migration checklist#

Do each of these before you start pulling mail out of Proton. Some are irreversible once the subscription lapses, so the order matters.

• Confirm your Proton plan. Bridge requires paid (Mail Plus, Unlimited, or Business); the free Export Tool works on any plan. If you planned to cancel first then export, reverse the order — Bridge stops when the paid subscription ends.
• Check Google-side storage. Personal Gmail is 15 GB shared with Drive and Photos; Workspace gives each user 30 GB and up. If your Proton archive is larger, buy storage before uploading — half-finished imports are the failure mode nobody warns you about.
• Export contacts as vCard and calendars as ICS from the Proton web app. Two minutes each; do them now so you don't forget on cutover day.
• Export your PGP keys if you use them. Proton Account → Encryption and keys → Export. Store somewhere you'll access after the subscription lapses — once closed, you cannot re-derive them.
• List every service using your Proton address as login or notification — banks, subscriptions, domain registrars, 2FA recovery. Anything sending a one-time code needs the new address before you close Proton.
• Decide the target Gmail address first. Personal @gmail.com and a Workspace address on a custom domain need different paths — DMS is Workspace-only; personal Gmail goes through a desktop IMAP client.

Path A — Export with Proton Mail Bridge (paid plans)#

Bridge is the cleaner path if your plan supports it. It runs on Mac, Windows, or Linux, decrypts your Proton mailbox locally, and presents a standard IMAP/SMTP endpoint on localhost. Point your desktop client at Bridge on one side and Gmail on the other, and drag folders between them.

1. 1

   Install Proton Mail Bridge and let it finish the first sync

   Download from proton.me/mail/bridge, sign in, and wait for the local cache to build. This can take an hour or more on a large archive. Connecting a client before it finishes produces authentication errors that look like a settings problem but are a timing one.

2. 2

   Add Proton to a desktop client via Bridge's local IMAP

   Thunderbird is the free option most guides use because it handles large IMAP moves gracefully. Bridge shows a per-account IMAP username, app-specific password, and local host/port. Add as IMAP using those values — not your Proton login password.

3. 3

   Add your Gmail or Workspace account to the same client

   For personal Gmail, enable IMAP in Settings → Forwarding and POP/IMAP first. For Workspace, IMAP is on by default unless an admin disabled it. Sign in through OAuth. Both mailboxes are now side-by-side.

4. 4

   Copy folders from Proton to Gmail in batches

   Drag or right-click-copy each folder from Proton to Gmail. Work in batches of a few thousand — clients handle small batches better than one gigantic copy, and if something fails partway you haven't lost the whole job. Gmail treats each destination folder as a label.

5. 5

   Verify counts on both sides after each batch

   Open source folder and Gmail label side by side, compare counts, and spot-check messages. Skip this and you'll only find out at cancellation time that a folder was truncated.

Path B — Export with the free Proton Mail Export Tool#

On Proton Free or after cancelling paid, Bridge is not available. The Proton Mail Export Tool is a small command-line app that exports your entire mailbox as EML with matching JSON metadata. Runs on Windows, macOS, and Linux, available on every plan.

1. 1

   Download the Export Tool from Proton's site

   proton.me/support hosts it under "Export Proton Mail messages". Verify against Proton's checksum. The tool is minimal — no installer, only a binary you run from a terminal.

2. 2

   Run the tool against a fresh empty directory

   It writes one EML per message plus one JSON metadata file, so the file count on a real mailbox is high. Point it at an empty directory with room for at least double your Proton usage.

3. 3

   Sign in with your Proton credentials in the tool

   It decrypts each message locally as it downloads. Nothing plaintext leaves your machine. If you have 2FA on, you will be prompted; the app-specific-password path Bridge uses does not apply here.

4. 4

   Let the export run to completion

   A large archive can take several hours. The tool is resumable — if the machine sleeps or the connection blips, restart it and it picks up. The JSON files preserve metadata a bare EML export would lose.

5. 5

   Import the EML files into Gmail via a desktop client's local folders

   Add the EML files to a Thunderbird or Apple Mail local folder (Thunderbird's ImportExportTools NG add-on; File → Import for Apple Mail), then drag the folder to your Gmail IMAP account. Slowest but most reliable — IMAP APPEND handles them one at a time and keeps original dates.

Importing into Gmail or Google Workspace#

Where mail lands next depends on whether you are moving to personal @gmail.com or a Workspace tenant. They look similar from the outside and are very different underneath.

1. 1

   Personal Gmail — upload through a desktop client

   Enable IMAP in Gmail Settings → Forwarding and POP/IMAP, sign into Gmail from Thunderbird or Apple Mail via OAuth, and copy folders from Proton (via Bridge) or local EML archives (via the Export Tool). Gmail's Import mail and contacts uses POP3, which Proton does not expose — and POP3 loses folders and flags anyway.

2. 2

   Google Workspace — use Data Migration Service against Bridge

   In the Workspace admin console, open Data Migration, choose Email, choose IMAP, and point at the Bridge local endpoint. DMS pulls folder-by-folder and preserves labels, dates and read state better than a manual desktop copy. Workspace-only; personal Gmail has no DMS.

3. 3

   Set up forwarding from Proton to Gmail during the cutover

   In Proton Mail → Settings → Filters → Auto-forward, add your Gmail address and confirm the code. Enable it before announcing the new address. This keeps new mail arriving in Gmail while contacts and services update.

4. 4

   Rebuild filters on the Gmail side

   Open Gmail Settings → Filters and Blocked Addresses (or Workspace routing rules) and recreate each Proton filter. Condition logic is similar; syntax is not portable. A document of the old filters is worth an hour of guessing.

5. 5

   Add your Proton address as a send-as identity in Gmail

   Gmail Settings → Accounts and Import → Send mail as → Add another email address. You can send from your Proton address through Gmail using Proton's SMTP (via Bridge) while the Proton account is active. Replies to old threads come from the address the sender remembers.

What breaks when you move Proton to Gmail#

Everything below is fixable. Knowing which items will hit you keeps this a two-week project, not a three-month one.

The diagram below shows what the export looks like — Bridge decrypts locally, the client or DMS is the transport, Gmail holds the plaintext copy.

The rollback plan#

Rollback is easier than most migrations, because Proton is untouched by the export — Bridge and the Export Tool read your mailbox, they do not modify it. Your Proton account is intact during and after the copy.

To reverse: stop the Gmail import, delete the Gmail labels you imported into (Manage labels → Remove label and messages), and keep using Proton. If you switched MX for a custom domain, point it back and give it 24 hours.

The one thing you cannot easily undo is Proton account cancellation — Proton deletes mailbox data on termination, no restore. Never cancel until Gmail has been primary for at least 30 days, the DMS run (if used) is verified, and EML files are stored outside both providers. Cancellation is the last step, not part of the cutover.

Doing it without downtime#

Technical downtime is zero — Proton stays reachable while you export, Gmail the moment the first message lands. The downtime that costs you is behavioural: mail to the wrong address for a week, or a one-time code arriving at Proton while you check Gmail.

• Set up Proton → Gmail auto-forwarding before announcing the new address. Senders who didn't get the memo still reach you.
• Monitor both inboxes in parallel for at least two weeks. Some transactional senders (banks, airline check-ins) hit the address directly; a fortnight surfaces every one.
• Work the address-change list in high-stakes order — banking first, then subscriptions and registrars, then everything else. Give each tier a couple of days.
• Announce the change in a short email from both accounts, so it lands whether the recipient has your old or new address. Say Proton still forwards, so early adopters don't think they broke something.
• Do not cancel Proton for at least 30 days after Gmail is primary, preferably 90. People will keep sending to your Proton address for months; the account staying open makes forwarding a safety net rather than a bounce.
• Keep an offline EML archive. Even if you cancel Proton and Gmail keeps the copy, an independent local archive protects against a lost Google account or corrupted Gmail label years later.

Where AI Emaily fits after the move#

Once your mail is in Gmail or Workspace, the next question is what runs on top — the client, the triage layer, the agent. AI Emaily is an AI email client that connects to Gmail and Workspace by OAuth, reads and writes through the Gmail API, and layers an approve-before-send agent, autonomy modes, and an audit trail on top. Nothing about the mailbox changes; the client and agent are the addition. We build AI Emaily.

It's the honest next step because people usually migrate off Proton for the ecosystem, then look at a client like ours because Gmail on its own does not triage, draft, or follow up. 7-day free trial on Pro or Autopilot (card required, $0 if cancelled before day seven) — check current tiers at aiemaily.com/pricing.