How do I move my Bitcoin to bit21?

You don't. Type your existing 12 or 24-word recovery phrase into bit21 and the same addresses appear, holding the same coins. Nothing moves on-chain, no fee, no waiting. About thirty seconds.

What does self-custody actually mean?

You hold the private keys. No company, no exchange, no government sits between you and your coins. If bit21 vanished tomorrow, your seed phrase still opens your wallet in any BIP39-compatible app.

What if I lose my phone?

Bitcoin is not stored on your phone. It lives on the network. The seed phrase is the key. Back the seed up on paper or steel and you can restore the wallet on any device, any time.

Does bit21 collect any data about me?

No account, no email, no phone number, no KYC. The wallet itself sends nothing identifying when it queries the blockchain. We have no list of users to leak even if we wanted to.

Which Bitcoin address types are supported?

All four standard types: Legacy (1...), SegWit Compatible (3...), Native SegWit (bc1q...), and Taproot (bc1p...). You can pick a type per wallet and bit21 finds funds across all of them automatically on import.

What is the Vault feature?

A vault uses Bitcoin's CheckLockTimeVerify opcode to make coins literally unspendable until a chosen block height. Bitcoin's own consensus enforces the lock. Not bit21, not us. Useful when you want to hold long-term and stop yourself from touching the stack early.

What is the time-locked vault for?

Forced patience. Lock a chunk of Bitcoin for a year, two years, whatever you need. The protocol holds it; nobody can unlock it early, including the people who built bit21. If you tend to fiddle with your stack during volatility, this removes the option.

Is bit21 open source?

Yes. The wallet code is public for anyone who wants to inspect or verify it. Most users use the official apps. The source is there if you ever care to look.

Can I use bit21 on iPhone?

Yes, through the web app at wallet.bit21.app. It runs in any modern browser, iPhone included. A native iOS app is in the pipeline.

Why Bitcoin only? Why not other coins?

Every extra coin adds code, complexity, and attack surface. Multi-chain wallets have more places to break. bit21 stays focused on Bitcoin because that is the asset that warrants this level of care. Not a limitation. A choice.

Yes. You pay standard Bitcoin network fees when you send a transaction; those go to miners. bit21 takes no cut.

Blog

Name: bit21 Bitcoin Wallet
Author: bit21

Guides, insights, and updates about Bitcoin self-custody.

June 8, 20266 min read

How to Back Up Your Bitcoin Seed Phrase the Right Way

Lost seed phrases are the single most common cause of permanent Bitcoin loss. A few words on paper stand between you and your sats forever. This is how to back them up so they survive fire, water, theft, and your own future mistakes.

June 6, 20266 min read

Bitcoin Time-Locked Vaults Explained: Lock Your Own Coins With CLTV

A time-locked vault makes your own Bitcoin unspendable until a future block height. Not by a company. By Bitcoin itself. Here is how CheckLockTimeVerify works, why it removes the temptation to sell, and what it does not protect against.

June 4, 20267 min read

Bitcoin Address Types Explained: Legacy, SegWit, Native SegWit, Taproot

Why does one Bitcoin address start with 1, another with 3, and another with bc1? Four address types, four sets of tradeoffs in fees and privacy. Here is what each one is, which to use, and why a good wallet supports all of them.

June 2, 20266 min read

What Is Coin Control and Why Every Bitcoin Holder Should Use It

Your wallet balance is not one number. It is a pile of separate coins called UTXOs. Spend them carelessly and you link your whole stack together for anyone watching the chain. Coin control is how you stop that. Here is how it works.

April 25, 20263 min read

The Wallet Code Is Now Public

For most users this changes nothing. For the small slice who care to verify rather than trust, the option now exists. A short note on why open code matters for self-custody wallets, and what bit21 publishing its source actually means.

April 14, 20266 min read

What Is a Self-Custody Bitcoin Wallet and Why It Matters

Your Bitcoin sits on a blockchain, not inside a wallet. The wallet holds your private keys. When you use an exchange like Coinbase or Binance, they hold those keys for you. They can freeze your account, get hacked, or go bankrupt. Self-custody means you hold the keys yourself.

April 12, 20268 min read

How to Move Bitcoin From an Exchange to Your Own Wallet

Keeping Bitcoin on an exchange is trusting a third party with your money. Moving it to a self-custody wallet gives you full ownership. This guide walks through the process step by step, from choosing a wallet to verifying your first withdrawal.

April 10, 20265 min read

Why a Bitcoin-Only Wallet Is More Secure Than a Multi-Coin Wallet

Every additional cryptocurrency a wallet supports adds code, dependencies, and attack surface. A wallet that handles 500 coins has 500 times more things that can go wrong. Bitcoin-only wallets focus all their engineering on doing one thing well.