What is a watch-only wallet and is it safe?

A watch-only wallet is a wallet app setup that tracks a crypto address without being able to spend from it. You give it public information only, such as an address or an extended public key, and it shows the balance and transactions. Since it holds no private keys, it can watch but never move funds.

What is a watch-only wallet on Trust Wallet?

Trust Wallet calls this feature a view-only wallet. You add it from the wallet settings by choosing to add an existing wallet, picking view-only, selecting the blockchain network and pasting a public address. Trust Wallet says this gives read-only access, so you can see the assets but cannot send or sign transactions, and the address does not need to be yours. Our guide to Trust Wallet covers the app more broadly.

What is a watch-only Bitcoin wallet and an xpub?

A single address is easy to watch, but modern Bitcoin wallets use a new address for each payment. To follow a whole account, Bitcoin wallets use an extended public key, or xpub. Trezor explains that an xpub can generate and view all the addresses a wallet account controls, under the BIP32 standard for hierarchical deterministic wallets.

Watch-only setups are common with hardware wallets. BitBox's support guide shows how to import an account into the desktop app Sparrow, using a descriptor or xpub. Sparrow then shows balance, history and receiving addresses with the device unplugged, but it cannot sign transactions. To spend, you still need the device that holds the keys.

Is a watch-only wallet safe?

A watch-only address on its own cannot be used to take your coins. Trezor states plainly that an xpub cannot be used to spend funds. Sharing a single public address is also normal, as our guide on sharing your wallet address explains.

The risks are about privacy and trickery:

• xpub privacy: anyone with your xpub can see your entire balance and transaction history, and Trezor notes that later consolidating coins does not hide that past.
• Server privacy: BitBox warns that if a watch-only wallet connects to a public server, the server can learn which addresses you look up.
• Unverified addresses: BitBox says viewing an address in a watch-only wallet is not the same as checking it on the hardware device, so it advises verifying receiving addresses on the device.
• Fake balance scams: Trust Wallet warns that scammers add a view-only wallet to a victim's app to make it look as if funds arrived, then demand a fee to "unlock" them. Trust Wallet says no unlocking is needed, so any such request is a scam sign.

Your seed phrase and private keys should never be entered into a watch-only setup, because the whole point is that it does not need them.