You set up a wallet. The wallet showed you 12 or 24 words and told you to write them down. Now you are looking at that list and wondering: what do I actually do with this? Where does it go? What if I lose it? What if someone finds it? This guide walks you through every part of that. No tech jargon. Just the steps that work.
What is a seed phrase backup, and why does it matter?
A seed phrase backup is a written record of the 12 to 24 words your wallet showed you when you set it up. Those words are the master key to your crypto. If your phone breaks, if you lose the device, if the app gets deleted, the backup is the only way to get your money back. There is no other path.
The words come from a list of 2,048 words defined by Bitcoin Improvement Proposal 39 (source: BIP-39 — Mnemonic code for generating deterministic keys). They look random but they are not random to your wallet. The words let any compatible wallet rebuild the same keys, the same addresses, and the same funds. So the backup is the entire wallet, written down in a form you can read. For more on what a seed phrase actually is at the protocol level, see our companion piece on what a seed phrase is.
That is why the backup matters more than the device. The device is a piece of hardware that can break. The backup is the thing that survives.
On Blofin's platform, a forgotten password is something support can resolve. A lost seed phrase is not. We see this in support tickets every week, and the conversation always ends the same way. There is no service the platform can offer because the recovery path was always meant to live in the user's hands. The choice to self-custody is the choice to own this risk personally, which is why the backup discipline matters more than the choice of wallet brand. For the broader picture of what self-custody actually requires, see our companion guide on what is self-custody.
What materials should you use to back it up?
Two practical options for almost every reader. Paper, for fast and cheap. Metal, for fire and flood and time. Anything else (phone photos, cloud notes, password managers) is not a backup. It is a leak waiting to happen.
Option | Cost | Survives | When to choose it |
|---|---|---|---|
Paper | Near zero | Daily wear, careful handling, decades if sealed and stored well | Starting out; small balance; learning the workflow |
Metal seed plate | $30 to $150 | Fire, flood, time, casual physical damage | Long-term holdings; balances you would not want to lose |
Anything digital | n/a | Nothing. Every digital copy is a risk | Never. Phone photos, cloud notes, screenshots all break the model |
Paper is fine to start with. A piece of card stock, a fine-tip pen, a sealed envelope. Most people will use paper for years without issue. The risk with paper is fire, flood, and slow ink fade across decades. If any of those scare you, you upgrade.
Metal seed plates are stainless steel or titanium plates where you stamp or punch the words into the metal itself. Reputable plates survive house fires, floods, and 20-plus years of storage with no degradation. They cost $30 for entry-level punch kits and run up to $150 for stamping kits with extra durability features. For our deeper look at metal options and how to choose one, see our metal seed phrase backup guide.
Whichever you choose, the same rule applies to both: at least two physical copies, in different physical locations. We come back to the where in a moment.
Hardware wallet users and software wallet users back up the same way. The seed phrase is the seed phrase. The wallet type only changes how you hold the keys day-to-day; it does not change the backup. For the bigger picture on each, see our hardware wallet guide and our software wallets guide.
How do you actually write down a seed phrase safely?
Five concrete steps. Do them in order. Do not skip step 4.
Step 1 / Read the words off the device, not off any other screen. When your wallet shows you the seed phrase during setup, read it directly from that screen. Do not let any setup app on your computer show you the words. Do not screenshot. Do not photograph. The fewer places those words exist in any digital form, the safer they are.
Step 2 / Write each word by hand. Pen or pencil on paper, or stamp into metal. Do not type the words into anything. Typing means the words pass through your keyboard, your operating system, possibly your clipboard, and potentially malware that watches any of those. Writing by hand keeps the words off the device entirely.
Step 3 / Write the word number next to each word. The order matters. Word 1, word 2, word 3, all the way through 12 or 24. The order is part of the key. If you write the words alphabetically or in the wrong order, the backup will not restore the wallet even though every word is correct. Number them as you go.
Step 4 / Double-check every word against the device. Read your written list back to the wallet's screen word by word. Match the spelling. Match the order. Match the count. This is the most common point of failure. A misspelled word, a missing word, or a swapped order means the backup looks right but does not work. Take the extra minute.
Step 5 / Seal it or stamp it. Paper goes into a sealed envelope so you can tell if anyone has opened it. Metal gets the punch or stamp completed. Then move on to storage, covered in the next section.
If any step felt unclear, redo it. The cost of redoing setup is a few minutes. The cost of a bad backup is everything in the wallet.
Where should you store the backup once you have it?
At least two physical locations, separated geographically. One copy near you so you can find it. One copy elsewhere so a single event cannot destroy both. The single most common mistake we see is one copy in one place, usually a desk drawer in the same house as the device.
Think about what you are backing up against. Pick locations that survive the events that worry you most.
Event | Survives if you have... |
|---|---|
Device fails or is lost | Any single copy of the seed phrase |
House fire | At least one copy outside the house, OR a metal seed plate in a fireproof safe |
Flood | At least one copy elevated and watertight, OR metal in a sealed container |
Burglary | A copy in a location the burglar cannot find or reach |
Accidental discard during a move | Multiple copies, labelled clearly enough that future-you knows what they are |
Your death or incapacitation | An inheritance plan that points a trusted person to the backup (see H2.7) |
Workable location combinations:
Sealed envelope in a home safe + sealed envelope at a parent's or sibling's house
Metal plate in a home fireproof safe + metal plate in a bank safety deposit box
Two metal plates in geographically separated properties you own or control
Avoid:
Both copies in the same building (one event takes both)
A workplace desk (you do not control who has access)
A glove compartment, gym bag, suitcase (mobile = high theft risk)
"Hidden" in a book or behind a picture (forgettable; non-trivial probability you discard the host object during a move)
Bank safety deposit boxes are a reasonable choice for one of your copies, with two caveats. The bank can lose access during natural disasters or system events. And in some jurisdictions law enforcement can request access. For most users this is acceptable for one of the two copies, not both. NIST guidance on key management treats key storage as a lifecycle that should include geographically separated copies for high-value assets (source: NIST SP 800-57 Part 1 — Recommendation for Key Management).
What should you never do with your seed phrase?
Five anti-patterns. Each one has a specific mechanism that breaks the backup. The fact that one of these is common does not make it safe.
Never photograph the seed phrase. A photo on your phone is a photo in iCloud or Google Photos a few seconds later. A photo in the cloud is a photo backed up across multiple servers, indexed for search, and exposed if the cloud account is ever compromised. Crypto wallet drainers actively scan compromised cloud accounts for images that look like seed phrases. This is not paranoia; it is documented behaviour.
Never type the seed phrase into a password manager or notes app. Password managers are well-built for passwords. They are not built for the master key to your entire crypto holdings. If the password manager service is breached, if your master password is phished, if a device is compromised while the vault is unlocked, the seed phrase is exposed. The trust model for password managers assumes individual credentials whose breach is recoverable. A seed phrase breach is not recoverable.
Never email the seed phrase to yourself. Email is permanently archived, searchable, indexed, and sometimes scanned by service providers for "helpful" features. Email is one of the most attacked surfaces in personal computing. Once a seed phrase has been in an email, it is in the inbox, the sent folder, the trash, the cloud backup, and any device that has synced the account.
Never share the seed phrase with anyone. Not support agents. Not wallet companies. Not friends "to help with backup." Not family members "in case something happens." Legitimate wallet providers will never ask. The reason for sharing always sounds reasonable in the moment; the breach always traces back to the share. If you want a trusted person to be able to recover funds if something happens to you, the answer is an inheritance plan (covered below), not telling them the words.
Never store the only copy in a digital file, even an encrypted one. Encrypted notes apps, encrypted vaults, encrypted PDFs all assume the encryption layer is the protection. If your device is compromised when you decrypt to view the file, the words are exposed. The seed phrase model assumes offline-only storage. Any digital form is a regression.
The single most common pattern we see in lost-seed support cases is a backup that started on paper, then migrated to a phone photo "just in case," then to a cloud notes app, then sometimes to a password manager. Each step felt convenient at the time. Each step also widened the attack surface to anyone who later got access to the cloud account. The seed phrase is exactly as safe as the weakest place it has ever lived. For the broader catalogue of beginner mistakes around self-custody, see our companion piece on common crypto mistakes beginners make.
How do you test the backup actually works?
This step is non-optional. Almost every beginner skips it. Do not be that beginner.
Before you put any real funds in the wallet, do the recovery test:
Step 1 / Wipe the wallet. On a hardware wallet, this is a factory reset from the device's menu. On a software wallet, this is removing the wallet from the app, or installing the wallet on a second device fresh.
Step 2 / Restore from your written backup. Read your seed phrase off the paper or metal you wrote. Type each word into the wallet's restore screen in order. Make sure the wallet matches the words you have written, including the order.
Step 3 / Confirm the same address appears. If the wallet is restored correctly, the first receiving address will match the address that appeared during the original setup. Compare the first few characters and the last few characters at minimum. If they match, the backup works. If they do not, something is wrong with your backup. Fix it before you fund the wallet.
Step 4 / Now you can fund the wallet. Send a small test transaction first. Confirm it arrives. Then send the rest. The cost of one extra small transaction is a rounding error compared to the cost of losing access to a fully-funded wallet because of a bad backup.
Repeat the recovery test every few years. Paper fades. Pens go dry over time. Metal plates can corrode in humid environments. A test every two or three years catches degradation before it becomes a loss. For the full recovery procedure if you ever actually need to use the backup for real, see our companion guide on how to recover a crypto wallet.
How does someone else recover your wallet if you can't?
The same way you would: by finding the seed phrase backup and following the same steps. But this only works if they can find it. Self-custody backup is also an inheritance question. Without a plan, the same design that keeps your funds safe from outsiders keeps them safe from your spouse, your children, and your executor.
The minimum viable inheritance plan has three parts:
Tell at least one trusted person the backup exists. Not the words. Just that there is a backup, what it is for, and that finding it is part of settling your estate. The trusted person should be someone who would actually act on this information, not someone who would forget by next year.
Write down where the backup is and how to use it. A sealed letter with your important documents, kept where the trusted person can find it. The letter should explain: the backup is the master key to a crypto wallet, here is where the paper or metal is stored, here is the wallet app to download, here is how to restore. Plain language. Someone non-technical should be able to follow it.
Do not tell the same person both pieces. The trusted person should know the backup exists and where it is, but the letter telling them how to use it should be somewhere they can find when needed (estate documents, lawyer's office), not somewhere they can casually access today. The trust model is that they have to wait for the situation to arrive before they can use the information.
This is the minimum. More elaborate setups use multisig with one key held by an estate attorney, or specialised crypto-inheritance services that combine cryptographic threshold schemes with legal estate frameworks. For the full inheritance planning depth, see our companion piece on crypto inheritance planning. For most users with single-signature wallets, the sealed-letter approach is the working starting point.
The failure to avoid: every person who knew the seed phrase is gone, and no instructions exist for anyone else. That is the inheritance gap that the QuadrigaCX case made famous at the custodian level, and it happens individually all the time.
Frequently asked questions about backing up a seed phrase
Can I store my seed phrase in a password manager?
No. Password managers are well-built for passwords, not for the master key to your entire crypto holdings. If the password manager service is breached, if your master password is phished, or if a device is compromised while the vault is unlocked, the seed phrase is exposed. The trust model for password managers assumes individual credentials whose breach is recoverable. A seed phrase breach is not recoverable. Keep the seed phrase entirely offline.
Should I keep all words in one location or split them?
Keep all words together in each location, but use multiple locations. Splitting the words manually ("first 6 here, last 6 there") creates a fragile system where losing one half loses the whole. Splitting only makes sense in a proper Shamir Backup scheme (source: SLIP-39 — Shamir's Secret-Sharing for Mnemonic Codes), and that is a specialised setup beyond standard BIP-39. For most users, full copies in geographically separated locations is the right answer.
Is a metal seed phrase backup worth the cost?
For balances above a few thousand dollars, yes. Metal plates ($30 to $150) survive fire, flood, and decades of time that paper does not. The cost is one-time. The discipline is identical to paper. The bigger question is whether your overall backup strategy is sound first. A metal backup with a single copy in a single location is still single-point-of-failure. Solve the strategy first, then upgrade the medium.
How many copies should I make?
Two minimum, three is comfortable, more starts increasing exposure. Each copy is a physical thing someone could find. Two well-placed copies in geographically separated secure locations is the standard. A third copy with a trusted family member or in a bank safety deposit box adds inheritance resilience without much added exposure. Beyond three, the marginal redundancy is small and the marginal exposure is real.
Can I use a sealed envelope in a home safe?
Yes, for one of your copies. A sealed envelope in a home safe is reasonable storage if the safe is rated for fire and ideally water. The seal lets you detect tampering. Pair it with a second copy in a different physical location: a relative's house, a bank safety deposit box, a second property you own. A home safe alone is single point of failure if the house burns down.
What if I want to upgrade from paper to metal later?
Easy. Stamp or punch the same seed phrase onto a metal plate. Verify each word matches the paper version. Then either keep both (paper as redundant copy at a third location) or destroy the paper version once you trust the metal. Do not destroy the paper until you have verified the metal independently with a recovery test on a wipe-and-restore.
What if I lose one of my backups?
Make a new copy immediately and put it in a new location. The seed phrase is still secure as long as nobody else found the lost copy. But you have now lost a layer of redundancy. The question is whether the lost copy was found by someone else, in which case the funds may already be at risk, or simply misplaced. If you have any doubt about discovery, the safer answer is to move the funds to a new wallet with a freshly generated seed phrase.
Researched and written by the Blofin Academy editorial team with AI-assisted drafting. Primary sources include BIP-39 (mnemonic code specification), NIST SP 800-57 Part 1 (Recommendation for Key Management), and SLIP-39 (Shamir's Secret-Sharing for Mnemonic Codes). All facts independently verified against cited documentation current as of May 2026.
This article is for informational purposes only and does not constitute financial, legal, or estate-planning advice. Seed phrase backup mistakes carry permanent consequences for your crypto holdings; you should conduct your own research and follow your wallet manufacturer's official documentation before relying on any backup for funds you cannot afford to lose. Blofin Academy content reflects the state of public information at time of publication; security best practices and the threat landscape change frequently.