Cold storage, explained

Crypto can sit in three different places, and the difference between them comes down to one question: who holds the keys. Here is what each option is actually for, what you give up in each, and when a hardware wallet is worth buying.

The three places crypto lives

These are not competitors and there is no winner among them. They are different tools for different jobs.

On an exchange

The platform holds the keys. You hold an account balance, and the exchange moves coins on your instruction. This is what makes an exchange convenient: you can trade in seconds, recover a lost password through customer support, and never think about seed phrases. It suits active trading and the working balance you are actually trading with. The tradeoff is the custody mechanic described in the next section.

In a hot wallet

A hot wallet is self-custody software, the category that includes wallets like MetaMask and Exodus. You hold the keys, but they live on an internet-connected device: a phone, a laptop, a browser extension. That is what makes a hot wallet the right tool for actually using crypto, connecting to applications, swapping tokens, paying for things, moving day-to-day amounts. The tradeoff is that the keys sit on a machine that also opens email and runs software, which exposes them to malware, phishing, and anything that compromises the device.

In cold storage

Cold storage means the keys are held offline on a dedicated device that signs transactions without ever exposing the keys to your computer. It suits long-term holdings you are not moving often. The tradeoff is that it costs money, adds a little setup friction, and puts the recovery phrase entirely in your hands.

What it means when the exchange holds the keys

This is the part most people have never had explained, and it is mechanical rather than dramatic. When your crypto sits on an exchange, the exchange controls the keys to the coins. Your balance is a claim against that company, an entry in its records saying it owes you a certain amount, rather than coins you hold directly. In normal operation the distinction never comes up: you withdraw, the exchange sends, the system works exactly as advertised.

Where the distinction does matter is in what backs that claim. Dollars in an insured bank account are covered by federal deposit insurance, and securities at a failed brokerage are covered by SIPC. Crypto is covered by neither. The FDIC states plainly that deposit insurance does not apply to crypto assets and does not protect against the failure of a non-bank company, including exchanges and custodians. SIPC does not protect digital assets that are not securities. Many people assume a safety net is there because it is there for every other financial account they hold. For crypto on an exchange, it is not.

None of that makes exchanges unsafe or means you should not use one. It means the sensible rule is to match custody to use. Active trading on a reputable exchange is completely reasonable, and so is leaving there what you are actively trading with. Holdings you intend to keep for years are a different job, and that job belongs in cold storage. Most people end up doing both.

Moving coins from an exchange to a wallet you own is not a sale and does not create a tax event on its own, though the record of the move matters later. We cover that in crypto and tax, explained.

Self-custody has its own failure mode

Being honest about this cuts the other way too: lost seed phrases and forgotten passphrases have permanently destroyed more crypto than exchange failures have, and there is no support line that can recover them. If you take the keys, you take the responsibility for backing them up properly.

Buy from the manufacturer's store

If you do buy a hardware wallet, where you buy it matters more than most people expect. A hardware wallet is a security device, and a device that passed through unknown hands before reaching you cannot be assumed to be untouched. The specific risks are tampered hardware and, more commonly, a recovery card that arrives already filled in, which is not a backup but somebody else's keys. Both manufacturers give the same guidance: buy from their own store or a reseller they list as authorized, and treat marketplace listings on general retail sites as unverified. That means no Amazon, no eBay, no third-party marketplace seller, however convenient.

If a device has already arrived and you want to check it before trusting it with anything, the signs of a prepared device and the manufacturers' own verification steps are in counterfeit hardware wallets.

Ledger and Trezor

These are the two established names, both legitimate and both well regarded. They are built on different philosophies, which is what should decide between them.

Ledger builds around a certified secure element, the same class of tamper resistant chip used in passports and bank cards, and supports a broad range of chains and tokens. Its devices pair with a phone, and the premium model adds Bluetooth and a larger screen for checking transactions on the device itself. The lineup runs from an entry model with a small screen to a premium model with a larger display.

Trezor builds around open source: the firmware and much of the hardware design are published, so the security claims can be audited by anyone rather than taken on trust. Its roots and its focus are Bitcoin, and its entry model is the cheaper way into hardware storage. The lineup runs from a straightforward entry model to a premium model with a colour touchscreen.

Choosing between them is mostly one question. If you hold Bitcoin above all and want security you or anyone else can inspect in the source code, Trezor fits better. If you hold assets across many chains and want to manage them from a phone, Ledger fits better. Either device does the core job, which is keeping keys off an internet-connected machine.

Where to buy

We earn a commission if you buy through the links below. It costs you nothing extra and it does not change what we recommend. Separately, and for reasons that have nothing to do with us, both links go to the manufacturers' own stores, because that is where the supply chain is verifiable.

Sources

• FDIC, What the public needs to know about deposit insurance and crypto
• SIPC, What SIPC protects
• Ledger, Best practices to securely buy your Ledger device
• Trezor, Is my device safe to use?

This page is educational. It explains how custody works and is not advice about your particular holdings, nor a recommendation to buy or sell any asset.