Guide
What is the Proton Mail attachment limit?
25 MB of attachments per e-mail sent, 50 MB received, 100 files at most, according to Proton’s help. Beyond that, send a link: up to 5 GB here, without an account.
The Proton Mail limit, plainly
| E-mail sent | 25 MB, all attachments together |
|---|---|
| E-mail received | 50 MB, all attachments together |
| Files per e-mail | 100 at most |
Sources: Proton help — October 2026.
How to send bigger
A TransferThing link
Drop the file here, paste the link into your Proton mail. Up to 5 GB, without an account for you or the recipient, stored in the EU. Not end-to-end encrypted.
A Proton Drive link
Proton documents sending large files with a Proton Drive public link, with an optional password and expiry. It uses your Drive storage.
Zip or split
A .zip barely shrinks videos, photos or PDFs. Several e-mails work, but your recipient has to put everything back together.
A free account to follow your transfers.
See what was downloaded, and find your links again.
Frequently asked questions
What is the maximum attachment size in Proton Mail?
25 MB of attachments per e-mail you send, 50 MB per e-mail you receive, and 100 files at most, according to Proton’s help.
Why does a file just under 25 MB still fail?
Proton’s help notes that encoding makes attached files a bit larger than on your device, so a file close to the limit can go over it.
Is a TransferThing link end-to-end encrypted like Proton Mail?
No. The files are stored in the EU and the link is private, with an optional password, but they are not end-to-end encrypted: the password closes access, it does not encrypt the files.
How do I send a large video from Proton Mail?
Drop it on TransferThing, copy the link and paste it into your Proton mail: up to 5 GB, without an account. The video is not recompressed.
Does the recipient need a Proton account?
Not for a TransferThing link: they download in their browser, without an account.
New transfer
Add your files
Add your files
One file, fifty, or .
- 5 GBper transfer, free
- 200files, folders included
- 3 daysthen everything is erased
- No accountnothing to create