This article covers signing a Bitcoin message with one of the next unused Bitcoin addresses in your account. The BitBoxApp automatically selects one of these addresses, and you can choose another unused address if needed. The signature proves that your BitBox02 wallet controls the selected address without sending Bitcoin or creating a transaction.
If you need to sign with a specific address that previously received or sent Bitcoin, this is not the correct workflow. Follow How to sign a Bitcoin message with a used address instead.
Before you begin
- Use the latest version of the BitBoxApp.
- Have your initialized BitBox02 ready.
- Open the Bitcoin account you want to use.
- Have the exact message requested by the exchange, broker, or service.
Sign the exact requested message
Do not change its spelling, capitalization, punctuation, or spacing. Any change produces a different signature and can cause verification to fail.
The BitBoxApp supports message signing with Native SegWit addresses beginning with bc1q. Make sure the requesting service supports this address format.
Sign a message with a new address
Use this procedure when no previously used address is required.
- Open the BitBoxApp and select the Bitcoin account you want to use.
- Click Account information.
- Click Sign message.
- Review the unused address selected by the BitBoxApp. If needed, choose another address from the next 20 unused addresses before signing.
- Enter the exact message you need to sign.
- Click Sign on device.
- Connect and unlock your BitBox02 if prompted.
- Review the address and message on your BitBox02. Confirm only if they match the request.
- Copy the address, original message, and generated signature from the BitBoxApp.
The message is now signed with the selected address. Send the address, original message, and signature exactly as displayed to the party requesting proof of ownership.
Do you need a new or used address?
- No specific used address is required: Continue with this article and use the new address selected automatically by the BitBoxApp.
- A specific previously used address is required: Follow How to sign a Bitcoin message with a used address.
The address must match
A signature proves control only of the address used to create it. A signature made with a different address will not satisfy a request for a specific address.
Sign messages safely
Signing a message does not send Bitcoin, change your balance, or reveal your private keys or recovery words. However, the result can be used as evidence that you control the selected address.
Understand the message before signing
Do not sign an unclear or unexpected message. If someone pressures you to act quickly or asks for your recovery words, stop and contact BitBox Support.
Frequently asked questions
Does signing a Bitcoin message send Bitcoin?
No. Message signing creates cryptographic proof of address control; it does not create a Bitcoin transaction or move funds.
Why does the BitBoxApp select a new address?
The Sign message workflow starts with one unused address selected automatically. If needed, you can choose another from the next 20 unused addresses in the account before signing. This workflow is intended for situations where no previously used address is required.
Can I sign with an address I already used?
Yes, but it uses a different workflow because previously used addresses are selected through View used addresses rather than being selected automatically. Follow How to sign a Bitcoin message with a used address.
Why does the signature verification fail?
The address, message, and signature must match exactly. Verification can also fail if the verification tool does not support Native SegWit addresses or the message-signing format.
Where was Bitcoin message signing introduced?
Bitcoin message signing was introduced in the BitBox 05.2026 Geneva update. For release background and other related BitBoxApp improvements, read BitBox 05.2026 Geneva update.