This article explains how to sign a Bitcoin message with a specific Bitcoin address that has already been used to receive or send Bitcoin. Use this workflow when an exchange, broker, or service requires proof of control of that exact used address.
Unlike the new-address workflow, this procedure starts from View used addresses so you can find the requested receive or change address before signing. If no previously used address is required, follow How to sign a Bitcoin message with a new address on your BitBox02 instead.
Before you begin
- Use the latest version of the BitBoxApp.
- Have your initialized BitBox02 ready.
- Know which Bitcoin account contains the used address.
- Have the exact address and message supplied by the exchange, broker, or service.
The address and message must match exactly
Use the requested address and do not change the message's spelling, capitalization, punctuation, or spacing. Any change can cause verification to fail.
The BitBoxApp supports message signing with Native SegWit addresses beginning with bc1q. Make sure the requested address and the service verifying the signature support this address format.
Sign a message with a used address
Use this procedure only when you need to sign with a specific address from your account's used-address history.
The following example uses a Bitcoin testnet address that was previously used in 2023:
tb1qaueaqg3nqtanqc074gzvpykgedwtede95gnyfh- Open the BitBoxApp, connect and unlock your BitBox02, and select the Bitcoin account that contains the address.
- Click Account information.
- Click View used addresses.
The View used addresses screen displays the previously used receive and change addresses belonging to the selected Bitcoin account. If you are unfamiliar with this view, see How to view used addresses in the BitBoxApp. You can browse the list or use the search field to locate the requested address.
- Browse the list or enter the requested address in the search field to locate it more quickly.
- Check that the search result matches the requested address. If it is not under Receive addresses, select Change addresses and search again.
- Click the matching address to expand its details.
Receive and change addresses
Receive addresses are shared to receive Bitcoin. Change addresses are generated automatically when change returns to your wallet. Both receive and change addresses belong to your BitBox02 wallet and can be used for message signing.
- Click Sign message.
- Verify that the signing screen shows the requested address.
- Enter the exact message you need to sign.
For this example, enter:
How to sign a used address.
- Click Sign on device.
- 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.
- Click Done.
The completed example contains:
Address:
tb1qaueaqg3nqtanqc074gzvpykgedwtede95gnyfh
Message:
How to sign a used address.
Signature:
H+YU23Gxj3CZEQ063K+U344/Ubasw66DYC07AC+QwsqsOhvHTGkZ6096Vrpvk/zA2R6WVUtpCSISBsKmQZaLEq0=The message is now signed with the selected used address. Send the address, the original message, and the generated signature exactly as displayed to the party requesting proof of ownership.
If you cannot find the address
- Confirm that you selected the correct Bitcoin account.
- If you use multiple Bitcoin accounts, check each account separately.
- Search both Receive addresses and Change addresses, as the requested address may belong to either category.
- Copy the address again from the original request to avoid a typing error.
Address history is account-specific. This also applies to wallets opened with an optional passphrase: a different passphrase opens a different wallet with different addresses.
Do you need a used or new address?
- A specific previously used address is required: Continue with this article and select the address through View used addresses.
- No specific used address is required: Follow How to sign a Bitcoin message with a new address on your BitBox02 and use one of the unused addresses offered by the BitBoxApp.
The address must match
A signature proves control only of the Bitcoin address used to create it. A signature made with a different address will not satisfy a request for a specific used address.
Sign messages safely
Signing a message does not send Bitcoin, change your balance, or reveal your private keys or recovery words. The resulting signature can, however, be used as cryptographic proof that you control the selected Bitcoin 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 message send Bitcoin?
No. Message signing creates cryptographic proof of address control; it does not create a Bitcoin transaction, change your balance, or reveal your private keys or recovery words.
Why is signing with a used address a different workflow?
The standard Sign message workflow only offers unused addresses. To sign with an address that previously received or sent Bitcoin, you must first locate that exact address through View used addresses.
Can I sign with a used change address?
Yes. If the change address belongs to the selected wallet and appears under Change addresses, you can expand it and select Sign message.
Why is the address missing?
The address may belong to another Bitcoin account, another passphrase wallet, or a different address category. Check each relevant account and search both receive and change addresses.
Can I edit the signature?
No. Copy the signature exactly as generated. Changing, removing, or adding even one character can make it invalid.
Where was signing with a used address introduced?
Signing Bitcoin messages with previously used addresses was introduced in the BitBox 05.2026 Geneva update. For release background and other related BitBoxApp improvements, read BitBox 05.2026 Geneva update.