Your seed backup isn't a backup until you've restored from it once

The standard advice stops too early. Write down your seed, store it somewhere safe, done. The step almost nobody does is check that the thing they wrote down actually works.

People find out years later. A missed word, two words swapped, a 6 that was a b. By then there's nothing left to compare against.

Testing costs almost nothing. Use a cheap second hardware wallet or a wiped spare phone. Restore from the written words only, not from anything still sitting on your main device. Then compare the first two or three receive addresses against your real wallet. If they match, the backup is proven. Wipe the test device and you're done.

If your wallet shows a master key fingerprint, usually labelled XFP and shown as 8 characters like A1B2C3D4, that's a faster check. Same seed and passphrase always produce the same fingerprint. One wrong word produces a completely different one. It comes from a public key, so it isn't secret and you can write it next to your backup.

The passphrase deserves its own warning. A wrong passphrase doesn't throw an error. It quietly builds a new empty wallet, so "my coins are gone" and "I typed one character wrong" look identical on screen. If your passphrase only lives in your head, your seed backup on its own recovers nothing. Back it up separately, in a different place to the seed.

Do the test once at setup, and again any time you rewrite or move the backup. Twenty minutes, and it's the only part of self custody you can prove works before you need it.