Satoshi test explained
A Satoshi test (also called a small deposit test or micro-transfer) is how many exchanges prove you control a self-hosted wallet when message signing is unavailable or unsupported for your chain.
What it is
The exchange shows a unique receiving address and an exact amount. You send that amount from the address being verified. Only someone who can authorize spends from that address can complete the payment, so a matching on-chain deposit is treated as proof of control. The EBA Travel Rule Guidelines list a predefined micro-transfer as an acceptable technical means of verifying self-hosted wallet control.
Typical steps
- In the exchange, choose Satoshi test / small deposit test for your private wallet.
- Copy the exact amount, asset, network and deposit address. Note the countdown (examples: Coinbase EU incomplete tests expire in 48 hours; Kraken and OKX document 180-minute windows).
- In your wallet, select the exact address (coin control on Bitcoin).
- Send the exact amount; pay the network fee separately so the received amount matches.
- Confirm “I’ve made the deposit” if the UI asks, wait for confirmations, then continue the withdrawal if the exchange requires a new request.
Where exchanges document it
- Coinbase — small deposit test
- Kraken — Satoshi test (EU/UK)
- Binance — Satoshi test / Travel Rule address book
- OKX — Satoshi test
- CoinJar Europe — Satoshi test option
Satoshi test vs message signing
Signing proves control without moving funds and usually has no network fee — prefer it when both your wallet and the exchange support it. Use a Satoshi test when signing is missing for your asset (Coinbase notes WalletConnect does not support Bitcoin message signing) or when the exchange only offers a micro-deposit path. More context: prove wallet ownership.
FAQ
Do I get the test amount back?
Usually yes as a credit on the exchange once the deposit confirms (Binance and Coinbase document crediting the test), but you still pay the network fee. Read your exchange’s article.
Why did it fail when I sent “about” the right amount?
Exchanges match an exact amount. If your wallet subtracts the fee from the send amount, the received value will be short. Pay the fee on top.
What if my Bitcoin wallet rotated addresses?
You must send from the exact address being verified. Use coin control in Sparrow or Electrum. Verification often applies only to that address unless the exchange later accepts an xPub.
Sources
- EBA Travel Rule Guidelines (EBA/GL/2024/11)
- Coinbase: Small deposit test
- Kraken: What is a Satoshi test?
- OKX: What’s Satoshi test
Not legal, tax or financial advice. Deadlines and refund rules differ by exchange — follow the in-app instructions.