A Satoshi test is a method used to prove that you control a specific Bitcoin address. It is commonly requested by exchanges or other services for address verification or withdrawal whitelisting.

In most cases, you are asked to send a small, exact amount of bitcoin from the address you want to verify. Typical scenarios include:

• You sent bitcoin to an exchange → the exchange asks you to verify the sending address
• You previously provided a receiving address → the service asks you to confirm ownership

Using coin control in the BitBoxApp ensures that the transaction is sent from the correct address by allowing you to select the exact coin (UTXO) linked to it.

Before you start

Make sure the following conditions are met:

• The address belongs to your wallet
• The address holds funds (a UTXO)
• Coin control is enabled in the BitBoxApp
• You have the exact recipient address and amount from the exchange

If you have not enabled coin control yet, see:
How to use coin control in the BitBoxApp

Check the address using a block explorer

Before performing the Satoshi test, verify the address to ensure it meets the required conditions.

A reliable and easy-to-use tool for this is a block explorer such as:
https://mempool.space

How to verify the address

1. Copy the Bitcoin address you want to verify
2. Paste it into the search field (top right corner)

3. Review the following details:
   1. Confirmed balance: Ensure the address holds funds (required for the test)
   2. Confirmed UTXOs: Verify that at least one UTXO is available on the address
   3. Transaction history: Confirm that the address has previously received funds and that the listed transactions match your own activity (transfers you recognize).

Example: Empty address

In this example, the following address was searched:
bc1qs6fn6c0060fllj8c5exmwysgrtuddlycausdat 

Key observations:

• Confirmed balance: 0 BTC → the address is empty
• Confirmed UTXOs: 0 → no spendable coins available
• Total received: shows past activity
• Pending / unconfirmed: indicates if funds are still in transit

Since this address has no UTXOs, it cannot be used for a Satoshi test yet.

Why this step matters

This verification helps you avoid common issues:

• Attempting a Satoshi test with an empty address
• Selecting the wrong address in your wallet
• Sending funds from an unrelated UTXO

If the address does not hold any funds, you must first send bitcoin to it before proceeding.

Fund the address (if it is empty)

If the address is empty (no balance or UTXOs), you must send a small amount of bitcoin to it before performing the Satoshi test.

This process also allows you to verify that the address belongs to your wallet.

Step 1: Open the send screen

1. Open the BitBoxApp
2. Select the account where the address should be
3. Click Send

Step 2: Enter the address

1. Paste the address you want to verify as the recipient.
2. Enter a small amount of bitcoin:
   1. Enough for the Satoshi test
   2. Enough to cover transaction fees
      1. Optionally, add a note such as:
         Satoshi test for [exchange name]

Step 3: Review and verify on your BitBox02

1. Carefully review all details in the BitBoxApp.
2. Then check your BitBox02 display.
   1. If the address belongs to your wallet, the device will show:

This BitBox (same account): bc1q…

Step 4: Confirm and send

If everything matches:

• Confirm the transaction on your BitBox02
• Wait for the transaction to be confirmed

Step 5: Verify the result

After the transaction is confirmed:

• Check your transaction history in the BitBoxApp.
  If you used a standard receiving address (not a change address), the self-transfer will appear as a new transaction.
• Open Coin Control to verify the result on a UTXO level.
  Here you can see exactly which coins (UTXOs) exist and which addresses they belong to.
• Confirm that a UTXO is now available on the address you funded.
  This proves the address is active and ready for the Satoshi test.

How to perform a Satoshi test

Step 1: Open the send screen

1. Open the Bitcoin account in the BitBoxApp that contains the address.
2. Click Send.

Step 2: Open coin control

1. Open coin control in the send window.

2. You will see a list of all available UTXOs and their associated addresses.

Step 3: Select the correct UTXO

Find the UTXO that belongs to the address you need to verify.

Select only this specific UTXO.

Step 4: Enter the test details

Enter:

• the recipient address provided by the exchange
• the exact BTC amount required

Optionally, add a note such as:
Satoshi test for [exchange name]

Step 5: Review and confirm

Carefully review:

• recipient address
• amount
• transaction fee

Then verify the same details on your BitBox02 trusted display.

If everything matches, confirm the transaction on the device.

Step 6: Wait for confirmation

After broadcasting the transaction:

• track it on https://mempool.space
• wait for confirmation

Most exchanges detect the transaction automatically.
If not, provide the transaction ID or explorer link.

Troubleshooting

You selected the wrong coin or the address is empty

If you used the wrong UTXO, the verification will fail.

After spending from an address, it may become empty. This is normal.

Explanation

Bitcoin uses UTXOs (Unspent Transaction Outputs):

• Each transaction spends entire “coins” (UTXOs)
• Any remaining amount is returned as change
• The change is sent to a new address

Example:

• You have 0.01 BTC on one address
• You send 0.002 BTC
• The remaining 0.008 BTC is sent to a new change address

This means the original address may no longer hold funds.

You entered incorrect details

If the recipient address or the amount does not exactly match the instructions, the Satoshi test will fail.

If only the amount is incorrect but the recipient address is correct:

• Contact the exchange and inform them that you sent a transaction with an incorrect amount
• Ask whether they received the transaction and how to proceed

In most cases, you will need to repeat the Satoshi test using the exact amount specified to complete the verification.

The transaction is unconfirmed

If the network is busy, confirmation may take longer.

Check the status on:
https://mempool.space 

In most cases, you only need to wait.

Frequently asked questions

I can’t find the address in coin control

If the address does not appear, it likely has no funds.

Check it on:
https://mempool.space 

If it is empty, fund it first.

Why is the exchange asking for this?

1. Proof of ownership (address control)
Bitcoin addresses don’t have names attached. By successfully sending or identifying a small transaction, you demonstrate that:

• You hold the private keys
• You can sign and broadcast transactions

2. Compliance / KYC requirements
In some jurisdictions, exchanges must verify that:

• You control the destination wallet
• Funds aren’t being sent to third-party or custodial wallets without transparency

This is often part of Travel Rule / AML (anti-money laundering) checks.

Is there a better way to prove ownership?

Yes. Message signing or address signing is a better method.

Advantages:

• no transaction fees
• faster verification
• no need to move funds

Ask your exchange if they support it.

Learn more:
Satoshi Tests hinder self custody, but AOPP can fix it! 

What if the address is a change address?

Change addresses are more difficult to verify because any remaining funds from a transaction are automatically sent to a newly generated address. These addresses are typically not clearly labeled in your transaction history.

Whenever possible, we recommend asking the exchange to return the funds and then performing the Satoshi test using a standard receiving address, as described in this article.

If returning the funds is not possible and you need to proceed with the change address, follow these steps:

1. Fund the address
   Ensure the change address holds a UTXO.
2. Use coin control
   Select the exact UTXO associated with the change address.
3. Perform the Satoshi test
   Send the required amount using only the selected UTXO.

The test still isn’t working

Before proceeding, double-check the following with your exchange:

• the exact recipient address
• the exact amount (including correct unit: BTC vs satoshis)
• any additional requirements (e.g. minimum confirmations or specific instructions)

If everything matches and the test still fails, please contact support and include:

• the exchange name
• the Bitcoin address you are trying to verify
• the transaction ID (if available)