Custodial vs. self-custody

Someone has to hold the keys to your coins. Either a company does it for you, or you do it yourself. Each choice removes one set of risks and adds another.

Custodial: a company holds the keys

When your crypto sits on an exchange or in a custody service, the company controls the private keys. You log in with a username and password, and the company moves coins when you ask.

What you gain

A familiar login, with password reset if you forget
Nothing to back up
Easy buying and selling

What you risk

US securities regulators sum it up: "If the third-party custodian is hacked, shuts down, or goes bankrupt, you may lose access to your crypto assets." The company can also freeze your account or pause withdrawals. Lesson 12 gave examples.

Self-custody: you hold the keys

In self-custody, the keys are in a wallet you control and the backup is your seed phrase.

What you gain

Nobody can freeze, lend out or lose your coins on your behalf
You can send at any time without asking permission
You are not exposed to a company's failure

What you risk

The same regulators: "If your crypto wallets are lost, stolen, damaged, or hacked, you may permanently lose access to your crypto assets." There is no helpdesk and no reset. A mistake is yours alone.

Side by side

	Custodial	Self-custody
Who holds the keys	The company	You
Forgot your login	Reset by email	No reset: you need the seed phrase
Company fails	Coins may be lost or frozen	No effect on you
You make a mistake	Sometimes fixable	Usually permanent
Main threat	The company and your account	Losing or leaking your seed phrase

"Not your keys, not your coins"

You will hear this slogan often. It makes a true point: a balance on an exchange is a promise, not possession.

It leaves out the other half. Self-custody has its own casualties: forgotten phrases, discarded hard drives and people tricked into typing their words into a fake site. Holding your own keys is safer only if you can do it carefully.

Which suits you?

Ask yourself:

Am I comfortable setting up and maintaining a wallet?
Can I store a seed phrase safely for years?
How much would it hurt to lose this amount?
Do I trade often, or hold for the long term?

Most people use both

A common arrangement:

On an exchange: a small balance for buying and selling
In self-custody: savings you do not plan to touch

You do not have to move everything at once. Lesson 35 walks through a first withdrawal using a small test amount.

There is also a third route. Exchange-traded funds that hold bitcoin or ether are sold through ordinary brokerage accounts. You own shares in a fund, not coins, and cannot send or spend them.