Your 24-word BIP-39 seed is the master key for every address your hardware wallet can create. If a thief copies that seed, you are finished. To add another wall of protection, many wallets let you hide a second secret behind the seed. Two styles dominate:
Manual passphrase
Stored 25th word
Both turn one seed into at least two wallets, but they do it in very different ways.
| Feature | Manual passphrase | Stored 25th word |
|---|---|---|
| How you set it | Type any ASCII string during each unlock | Enter one extra word once during setup |
| Where the secret lives | Only in your head or on a backup plate | Encrypted inside the wallet’s secure element |
| Daily use | Re-type phrase every time you connect | Select a second PIN or fingerprint, no typing |
| Number of hidden wallets | Unlimited | Only one at a time |
Manual passphrase feels like a password you type repeatedly. Careful with relying on memory for safekeeping because if you become incapacitated, your crypto is lost.
Stored 25th word feels like an extra key that stays inside the lock and only turns when you use a special PIN.
Stored 25th word
During setup you enter the standard 24 words, then one more secret word.
The secure element converts those 25 words into the master seed and seals the result behind encryption.
From that moment on, the wallet never reveals the seed or the 25th word. It only derives private keys inside the chip and returns signatures to your computer or phone.
If the device breaks, you must recover with the written 24 words plus that 25th word because the device cannot show them later.
Manual passphrase
You finish the normal 24-word setup. Nothing extra is stored.
Every time you unlock, you type a passphrase. The chip combines that passphrase with the seed to create a brand-new wallet on the fly, signs the requested transaction, then forgets the passphrase until next time.
Lose the passphrase and those hidden funds are gone. There is no copy in the chip.
| Brand | Manual passphrase | Stored 25th word | How to reach the hidden wallet |
|---|---|---|---|
| Trezor | Yes | No | Type the phrase on device or computer each session |
| OneKey | Yes | No | Type the phrase on computer or phone each session |
| Ledger (default) | Yes | No | Same flow as Trezor and OneKey |
| Ledger “Attach to PIN” | No typing | Yes | Power up, enter the secondary PIN you created during setup |
| D’Cent | No | Yes | Enter main PIN and touch fingerprint sensor |
Attach to PIN on Ledger means you create a secondary PIN code and link one stored passphrase to that PIN. Enter the normal PIN to reach the everyday wallet, or enter the secondary PIN to open the hidden wallet that uses the passphrase stored in the chip.
| Scenario | Manual passphrase | Stored 25th word |
|---|---|---|
| Thief finds only your seed plate | Still needs passphrase | Still needs word 25 |
| You forget the secret | Hidden wallets lost forever | Hidden wallet locked, but you can recover if the device is still working and unlocked |
| Brute-force risk | Negligible if phrase is long | Negligible if word 25 is random |
Misplacing a manual passphrase is final, while misplacing a stored 25th word can be survivable when your hardware wallet remains intact and unlocked. Create multiple seed phrase backups to prevent a single point of failure secured by a passphrase that is both memorized and stored separately.
Never engrave the seed and the secret on the same steel plate.
Two-plate plan: Plate A is the 24 words, Plate B is the passphrase or 25th word. Store them in different buildings. Check out Black Seed Ink's Passphrase wallet for safe backup and protection against, fire, water and corrosion.
Simple inheritance: give Plate A to the executor and Plate B to an heir.
Multisig and secret: use three different brands in a 2-of-3 vault, then store the secret plate with a lawyer. Heirs need two devices plus the secret plate to move the funds.
| Factor | Manual passphrase | Stored 25th word |
|---|---|---|
| Hidden wallets available | Unlimited | One |
| Daily typing | Required | None |
| Risk of forgetting | Very high | Moderate |
| Ideal user | Needs many decoy or accounting wallets | Wants one deep vault with low friction |
| Brands offering it | Trezor, OneKey, Ledger default | D’Cent, Ledger attach to PIN |
Daily DeFi trader – Ledger attach to PIN or D’Cent for quick access and less typing.
Long-term HODLer who wants separate vaults or decoy wallets – Manual passphrases on Trezor, OneKey, or Ledger provide unlimited hidden wallets so you can segregate funds by purpose without ever sharing a seed or secret with anyone.
Long-term saver and estate planner – Either method works, but combine with multisig so no single person can empty the estate.
Can you remember or securely store the extra secret?
How often will you unlock the wallet?
Do you need multiple hidden wallets or just one?
Will heirs be able to locate both the seed and the secret?
Pick the style that you and your heirs can execute during a stressful emergency. A secret that is easy to use yet impossible to lose should be the goal.
This article is for education only. It is not financial advice. Test with small amounts and consult a qualified professional before finalizing any security or inheritance plan.
