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Lesson 2 · Recovery Security

Seed phrase security

A seed phrase can restore control of a Bitcoin wallet. It is one of the most sensitive pieces of information in a self-custody setup and must be protected from both loss and exposure.

Essential security lesson8–10 minute readNever share recovery words

Seed phrases in simple terms

The backup that can recreate your wallet

A seed phrase is a sequence of words generated by a Bitcoin wallet. It is used to derive the private keys controlled by that wallet.

The phrase may be shown as 12, 18 or 24 words depending on the wallet. The exact words and their order are essential.

If the original device is lost or damaged, the seed phrase can normally restore the wallet on compatible software or hardware.

Critical warning

Anyone who obtains your seed phrase may be able to take control of the wallet without your permission.

Why it matters

Protect against loss and theft

It is a recovery backup

A seed phrase can recreate the wallet's private keys and restore access to the associated bitcoin.

It must remain private

Anyone who obtains the full phrase may be able to recreate the wallet and spend the funds.

It is not a password reset

There is usually no company that can cancel, replace or recover a lost self-custody seed phrase.

It must be copied exactly

The words, spelling and order must be recorded accurately for reliable recovery.

If the wallet fails

The seed phrase may allow you to restore the same wallet on a replacement device.

If the phrase leaks

The wallet should be treated as compromised, even when no funds have moved yet.

What never to do

Keep recovery words offline

Most seed phrase theft occurs because the words are copied onto an internet-connected device or entered into a fake recovery process.

Never photograph it

Phone photos may be copied to cloud backups, viewed by apps or exposed if the device is compromised.

Never store it in cloud notes

Email, cloud drives, password-free notes and messaging apps create unnecessary online exposure.

Never type it into a website

A legitimate recovery process should only occur inside trusted wallet software or on the intended signing device.

Never share it with support

Wallet companies, exchanges and technical support staff do not need your recovery phrase.

Simple rule

Do not type your seed phrase into a website, chat, email, cloud document or support form.

Backup methods

Choose a durable physical backup

Paper backup

Write the phrase clearly on durable paper and store it in a secure, private location.

Strengths

Simple and inexpensive

Easy to read during recovery

No electronic exposure

Weaknesses

Vulnerable to fire and water

Can fade or tear

Easy to lose or photograph

Metal backup

Record the phrase using a purpose-built metal plate or stamped metal system.

Strengths

More resistant to fire

More resistant to water damage

Suitable for long-term storage

Weaknesses

Higher cost

Can still be lost or stolen

Incorrect stamping can cause recovery problems

Multiple physical copies

Keep carefully controlled backups in separate secure locations to reduce single-location risk.

Strengths

Protects against one location being destroyed

Improves recovery resilience

Useful for disaster planning

Weaknesses

Each copy creates another theft risk

Locations must remain private

Copies must remain identical and current

Secure storage

Protect the backup without making recovery impossible

Private

The location should not be visible or accessible to visitors, workers or casual observers.

Durable

The backup should survive the environmental risks expected at the storage location.

Recoverable

You or the intended beneficiary must be able to locate and understand the backup.

Separated

Avoid storing the wallet device and its only recovery backup together.

Documented

Keep clear recovery instructions without exposing the phrase itself.

Tested

Verify that the recorded phrase can restore the wallet before relying on it.

Physical hazards

Consider fire, flood, humidity, theft, accidental disposal and unauthorised discovery.

Access planning

Security should not be so complicated that you or your intended beneficiary cannot recover the wallet.

Recovery testing

Verify the backup before relying on it

A backup that has never been tested may contain a missing word, spelling mistake or incorrect order.

01

Start with a new or low-value wallet

Practise recovery before using the wallet to secure a significant amount of bitcoin.

02

Confirm the phrase was recorded correctly

Check every word, spelling and position against the wallet's original backup screen.

03

Use the wallet's recovery-check feature

Many hardware wallets provide a safe on-device method to verify the backup.

04

Avoid entering the phrase into a normal computer

Use the intended secure recovery flow whenever the wallet supports it.

05

Confirm the same wallet is restored

Verify that the expected addresses or a small test balance appear correctly.

06

Return the backup to secure storage

After testing, ensure the phrase is not left visible, copied or exposed.

Use the safest available method

When a hardware wallet offers an on-device backup check, use that feature rather than typing the phrase into a normal computer.

Phishing warnings

No legitimate person needs your seed phrase

A message claims your wallet must be verified immediately

A website asks for all recovery words

A support agent offers to restore the wallet for you

An app claims a seed phrase is required for a software update

A person sends a recovery form or online backup tool

A device arrives with words already printed inside the package

Loss and exposure

What to do when something goes wrong

Wallet device is lost or broken

The seed phrase can normally restore the wallet on a compatible replacement device or wallet.

Seed phrase is lost but the wallet still works

Create a new wallet with a new backup and transfer the funds before the device fails.

Seed phrase is exposed

Treat the wallet as compromised and move funds to a newly created wallet with a new seed phrase.

Both wallet and phrase are lost

The bitcoin may be permanently inaccessible because no recovery authority exists.

Exposed phrase

A seed phrase cannot be made secret again after it has been exposed.

Create a new wallet with a new seed phrase and transfer the funds to the new wallet as soon as it is safe to do so.

Lesson summary

The important points

A seed phrase can recreate the wallet's private keys.

Anyone who obtains the phrase may be able to spend the funds.

Keep recovery words offline and never type them into websites or support forms.

Use a durable physical backup stored in a private location.

Test the recovery process before storing significant funds.

Treat an exposed seed phrase as permanently compromised.

If both the wallet and every backup are lost, recovery may be impossible.