Storing your seed phrase safely.

A photo of a seed phrase, a text file on a computer, a note in a cloud app, or a password manager connected to the internet: all of these bring the words within reach of systems that can be attacked remotely. Malware that specifically searches for patterns of 12 or 24 words on an infected computer is a well-known and widely used attack technique.

Even a seemingly harmless backup, such as an email to yourself or a note in an unencrypted app, can be enough to give an attacker access once that one inbox or account is compromised. The principle is simple: a seed phrase should only ever exist on physical, offline media.

The simplest method is writing the words down by hand on paper, for example the card provided with a hardware wallet. Paper is cheap and quick to use, but vulnerable to fire, water damage and physical wear over long periods.

For those planning a longer storage horizon, metal backup plates are an alternative: the words are stamped or engraved into a corrosion-resistant metal plate, which withstands fire and water damage far better than paper. These solutions cost somewhat more and take a bit more time to set up, but significantly reduce the risk of loss from environmental factors.

A single copy in a single location is vulnerable: a house fire, burglary, or simple misplacement can permanently cost you access to your funds. Many users therefore keep multiple copies in physically separate locations, for example a home safe and a safety deposit box at a bank or with a trusted family member.

When spreading copies, it is important to strike a balance: too many copies in too many places increases the risk that one is found by someone else, while too few increases the risk of permanent loss. A common approach is two to three copies, each in a location known only to you (and possibly a trusted person for inheritance purposes).

If you suspect a seed phrase has been compromised, for example after a phishing attempt where you entered the words on a suspicious site, the only safe response is moving all funds to an entirely new wallet with a freshly generated seed phrase. A compromised seed phrase cannot be 'fixed' or changed; the words remain valid for that specific wallet forever.

Do this as quickly as possible, since an attacker who knows the words can move the funds at any moment. Do not wait for further signs of misuse.

A seed phrase hidden so well that no one could ever find it is a real risk in the event of death or serious illness. Some people therefore leave instructions with a notary, a sealed envelope with family, or use specialised digital-inheritance services.

A practical middle ground is recording part of the information, such as the location of the backup rather than the words themselves, in a will or with a trusted person, so access remains possible without undermining security during your lifetime.