Proton Wallet

Proton Wallet is a free Bitcoin wallet made by Proton Financial AG, a Swiss subsidiary of Proton AG. It launched in early access in July 2024 and opened to everyone in February 2025, and runs on Android, iPhone and the web. It holds Bitcoin only, and you sign in with a Proton account.

Proton calls it a self-custody wallet: the keys are made on your device and Proton says it cannot spend your coins. That is Proton’s statement, and Proton’s page of audit reports lists none for the wallet. Bitcoin transactions are public on the blockchain for anyone who knows an address, so the wallet can only avoid adding leaks. Its main weakness there is that everything you look up goes through Proton’s servers.

Who Holds the Keys

Each wallet has its own 12-word seed phrase in the standard BIP39 format, so the funds can be restored in any wallet that accepts such a phrase. The app does not show the phrase when you create the wallet. Saving it is a step on a checklist that you can leave undone, and you display the phrase later in the wallet’s settings after entering your account password. Proton’s help pages say it is a last resort that restores the coins but not the notes and Bitcoin via Email messages attached to the wallet.

Proton keeps an encrypted copy of the phrase for you. Your device encrypts it with a wallet key, the wallet key is encrypted with a key that your account password unlocks, and Proton’s servers store only the encrypted forms. By Proton’s account, it cannot read them. The consequence is that the account is a way into the wallet: the 12-word Proton account recovery phrase, which you can switch on separately, restores your account including the wallets, and Proton’s help pages warn that anyone who knows it can take over your wallets. Turning on two-factor authentication matters more here than in a wallet that lives only on a phone.

An optional passphrase turns the same phrase into a different wallet. You can only set it when you create a wallet, not for the first one, and Proton never stores it; a lost passphrase cannot be recovered. If you lose your account password, the Proton recovery methods and the seed phrase, nobody at Proton can restore your coins, and the terms say the same. The wallet has no multisig.

What Proton’s Servers See

The wallet does not run its own copy of the blockchain. The apps ask Proton’s own Bitcoin nodes for your history and balance, and Proton says its servers can see which addresses are queried, though it says it does not store those queries or your balances. It does store your transaction IDs and notes, encrypted. Because you sign in with a Proton account that has an email address, your queries are tied to that account rather than to an anonymous connection.

There is no setting for your own node, no built-in Tor and no coin control, so you cannot choose which coins a payment spends. If you need a way to look up your coins without telling one company about them, this is the wallet’s biggest limit.

Crash reports and usage diagnostics are switched on by default for a new Proton account, and you can switch them off in the account’s privacy settings. Proton’s privacy policy says its apps do not access or track the location of your device.

Bitcoin via Email

Bitcoin via Email lets you send bitcoin to an email address instead of a Bitcoin address, as long as the recipient also uses Proton Wallet and has the feature switched on. The recipient’s account keeps a pool of unused addresses, each signed with their email key, and the sender gets a different one every time, so two senders cannot easily see each other’s payments. Proton’s own security notes say that once someone links those addresses on the blockchain, for example by moving the coins together, the separation is gone.

Proton’s servers know the sender’s and recipient’s email addresses during a send but do not store them. The recipient has to be logged in and active so that new addresses can be made, and if the pool runs out while they are offline nobody can pay them. Creating an extra email address for it needs a paid plan; the free plan comes with one.

Buying Bitcoin

The Buy button first asks for your country, then shows a partner company that sells the bitcoin and sends it to your wallet. Proton’s help pages name Banxa and Ramp, and the terms also name MoonPay. Banxa says a first-time buyer completes a one-time identity check with a photo ID, a process known as KYC. You can also fund the wallet by receiving coins from elsewhere. Proton does not name a fee of its own for buying; the partner’s price is in the quote shown before you pay.

Open Source and Audits

The phone app, the web app and the Rust libraries under them are public on GitHub under the GPL v3 open-source licence. Proton’s server code is not published. The Android app can be built from the public code with Docker instructions; the iOS instructions are listed as work in progress, and Proton does not offer reproducible builds, so you cannot check that a store app matches the code.

Proton’s page of audit reports lists reports for its mail, calendar, drive, VPN and password apps and for its encryption libraries, and none for Wallet. Wallet is covered by Proton’s public bug bounty. A missing report does not mean a problem, but it means the claim that nobody but you can reach your keys rests on Proton’s word and on code you would have to review yourself.

Incidents and Vulnerabilities

Wallet’s incident history has one entry. On 25 July 2024, researchers at the security firm Zellic reported to Proton that the phone app made two secrets with Dart’s non-secure random function: the key that encrypts the stored wallet phrase and the account recovery phrase. On phones, those had about 32 bits of randomness, which the researchers could guess in around 16 minutes on a desktop computer. The wallet’s seed phrase itself was made securely.

According to the researchers, the weak key protected data stored on Proton’s servers, so someone with access to that data, such as an insider or an attacker with database access, could have decrypted wallets; Proton’s captchas made guessing weak recovery phrases from the internet harder. Proton fixed the generator the same day, found out on 15 August 2024 that phones were affected more than expected, invalidated the weak recovery phrases, blocked the vulnerable app version and re-encrypted existing wallets with new keys. The researchers’ report says the recovery-phrase flaw was present for one day in a preview build and does not describe any wallet being compromised.

Ownership and Jurisdiction

The terms name Proton Financial AG, a Swiss company wholly owned by Proton AG, and its privacy policy gives an address in Baar. Proton AG’s main shareholder is the non-profit Proton Foundation, and Proton says no change of control can happen without the Foundation’s consent. Proton says it discloses the limited data it holds only on a binding request from Swiss authorities.

Apps and Networks

Proton Wallet runs on Android, iPhone and in a web browser, with no desktop app. It supports Bitcoin only. Each account can hold several wallets, and each wallet several Bitcoin accounts, within your plan’s limit.

Price

The wallet is free, with 3 wallets of 3 accounts each. Proton Unlimited raises that to 10 wallets with 10 accounts each; it costs US$119.88 for 12 months at the price shown at sign-up, and it is mainly a bundle of Proton’s other services. Visionary, the top plan, allows 50 wallets with 50 accounts each for US$359.88 a year at the same sign-up prices. Proton’s help pages say the network fee goes to miners, not to Proton, and name no fee of Proton’s own for sending or receiving.

Pros and Cons

Our Rating

Proton Wallet suits people who already use a Proton account and want a simple, free Bitcoin wallet with email payments, and who are comfortable with Proton seeing their lookups. It does not suit anyone who wants to use their own node or Tor, choose the coins a payment spends, or rely on an independently audited wallet.