This article shows you how to enable and use coin control in the BitBoxApp.
Once the feature is enabled in the settings, you can open the coin control panel while preparing a bitcoin transaction and manually choose which UTXOs to spend.
This can be useful if you want to send specific coins, avoid combining certain funds, or simply have more control over how a transaction is built.
If you are looking for a general explanation of what coin control is and why it can be useful, see What is coin control and why use it?
How to enable coin control
To use Coin Control, you first need to enable it in the BitBoxApp settings.
- Open the BitBoxApp.
- Click Settings in the bottom-left corner.
- Open Advanced settings.
- Find Enable coin control.
- Turn the toggle on.
Once enabled, the feature becomes available on the send screen of your Bitcoin account.
Don’t see the feature?
Coin control is only visible while preparing a bitcoin transaction. You will not see it directly in the account overview or settings after enabling it.
To open the coin control panel and view your UTXOs, you do not need to enter a recipient address or an amount. If the Remember Wallet (watch-only) feature is enabled and you only want to view your UTXOs, connecting the BitBox02 hardware wallet is not required.
How to find and use coin control in the BitBoxApp
After enabling the feature, coin control appears when you create a bitcoin transaction.
Open the coin control panel
- Open the BitBoxApp.
- If the watch-only feature Remember Wallet is not enabled, connect your BitBox02 and unlock it.
- In the left sidebar, select the account you want to send from, then click Send.
- Click coin control to open the coin selection panel.
You will then see a list of available UTXOs that you can manually select for the transaction.
Select your coins
In the coin control panel, you can see your available UTXOs and related information, such as:
- label or note, if available
- BTC amount
- fiat value
- date
- receiving address
- outpoint
Select one or more UTXOs by clicking the checkbox next to them.
Review labels carefully
If your wallet contains coins from different sources, labels can help you avoid spending the wrong UTXOs together. See also Managing wallet labels (BIP-329).
Choose how to send
You can use coin control in two ways.
Send a specific amount
Enter the recipient address and the amount you want to send, then select enough UTXOs so their total value covers:
- the amount you want to send
- the network fee
Sending a specific amount can be useful for regular payments or for ownership proofs, such as a Satoshi Test.
If the selected coins are worth more than the amount you send, the remaining bitcoin is returned to your wallet as change.
Good to know about change
The returned change is not shown as a separate incoming transaction in the main transaction history overview of the BitBoxApp. You can see it in the coin control panel, where the corresponding UTXO is marked with the blue label Change address.
Send the full value of selected coins
You can also send the full value of the selected UTXOs, minus the transaction fee.
This is useful if you want to:
- consolidate coins
- move selected UTXOs to another wallet
- transfer selected funds without creating additional leftover UTXOs from other inputs
Finalize the transaction
- Review the transaction summary in the BitBoxApp.
- Verify the recipient address, amount, and fee on your BitBox02 screen.
- Confirm the transaction on the device.
UTXO selection is permanent once spent
Once a transaction is confirmed, the selected inputs become linked on the blockchain. Always review which UTXOs you are combining before sending.
Frequently Asked Questions
I enabled coin control, but I still can’t see it. Where is it?
Coin control only appears while preparing a bitcoin transaction. Open a Bitcoin account, click Send, and then open the coin control option from the send screen.
Can I disable coin control again?
Yes. Go back to Settings > Advanced settings and turn off Enable coin control.
What happens if I don’t select enough coins?
The BitBoxApp will not let you continue until the selected UTXOs cover both the amount you want to send and the network fee
What happens if I click on “Send all” without using coin control?
When coin control is not active, the checkbox on the send screen is labeled Send all. Ticking this box creates a transaction that sends the entire balance of that account to the recipient you entered. The BitBoxApp will automatically select all the necessary coins (UTXOs) to do this.
Do I need to choose a change address manually?
No. The BitBoxApp handles change automatically and sends the remainder back to your wallet if needed.
What do the labels “Change” and “Address re-used” mean in the coin control window?
Pay attention to the labels shown next to each coin:
- The blue Change label indicates a UTXO that comes from the change of a previous transaction.
- The red Address re-used label is a privacy warning. It indicates that the associated address has been used more than once.
These labels help you better understand your UTXOs and choose them more consciously.
Can I view my UTXOs without connecting my BitBox02?
Yes, if Remember Wallet (watch-only) is enabled. In that case, you can open the coin control panel and view your available UTXOs without connecting the BitBox02. To sign and send a transaction, you still need the device.