Self-hosted wallet: how to prove it belongs to you

Self-hosted wallet: what does it mean?

A self-hosted wallet is one where you hold the keys yourself: an app on your phone or computer, or a dedicated hardware device. No provider holds your crypto for you. It is the opposite of an account on an exchange, where the provider holds the keys and keeps track of your balance.

EU law speaks of a “self-hosted address”: a blockchain address that is not linked to any crypto-asset service provider. The distinction matters, because traceability rules do not work the same way when your crypto comes from a platform or from your own wallet.

• Address: the public identifier that crypto is sent to.
• Private key: the secret that lets you spend the funds at an address and sign messages.
• Recovery phrase: the list of words that restores your keys; whoever holds it controls the wallet.
• Transaction ID (hash): the unique reference of a transfer on the blockchain.

Why you need to prove your wallet belongs to you

Since 30 December 2024, Regulation (EU) 2023/1113 on transfers of funds, known as the TFR, has required every crypto-asset transfer to carry information on its originator and its beneficiary. Between two providers, this information travels with the transfer.

A self-hosted address has no provider to send that information. The regulation therefore sets its own check: for a transfer above €1,000 from such an address, the provider receiving the funds must take measures to verify that the address is owned or controlled by its customer (art. 16(2)).

This article explains the regulatory concept of wallet ownership and methods used by providers. It does not add a step to the CryptoIBAN account activation process.

For CryptoIBAN activation: Enter your first and last name, then make an initial deposit of at least $500. Your IBAN is usable after payment confirmation. For a payment, follow the exact amount and network shown in the deposit modal. The small test transfers described below are general examples, not deposit instructions.

The two common methods

Providers mainly use two methods. Both prove the same thing, control of the address, but they differ in effort and cost.

Message signing is the most discreet: nothing moves on the blockchain. The test transfer is the most universal: every wallet can send funds, even one that cannot sign a message.

When you have the choice, start with the signature: it costs no network fee and moves no funds. The test transfer remains the option for wallets that cannot sign, or when the provider asks for it.

Signing a message, step by step

A signature proves that you hold the private key to the address, without ever revealing it. It moves no funds and costs no network fee.

If your wallet shows you a transaction to approve, or a permission to spend your tokens, when you were asked to sign a message: stop. That is not proof of ownership.

1. The provider tells you which address is concerned and the exact text to sign.
2. Open your wallet and select that address.
3. Use your wallet’s message-signing feature, if it has one.
4. Paste the text without changing anything: a single extra space is enough to invalidate the signature.
5. Check on the wallet screen, or on the hardware device, that this is a message and not a transaction, then sign.
6. Copy the resulting signature and submit it through the provider’s interface.

The small test transfer, step by step

This method works with every wallet. It proves control of the address through a real transfer, sent from that exact address.

The test costs a network fee, like any transfer. If you plan regular deposits from the same address, ask the provider whether the verification remains valid for later deposits.

1. Note the provider’s instructions: asset, network, amount and destination address.
2. Send from the address being verified, not from another address or from an exchange.
3. Select exactly the asset and network specified.
4. Keep the transaction ID (hash) and share it if asked.
5. Wait for the provider’s confirmation before sending a large amount.

Common mistakes

These mistakes are easy to avoid. The last one is by far the most serious.

If a request looks odd, stop and contact the provider’s support through its usual channel, never through a link received by message.

• Editing the text to sign (a space, a line break, a capital letter): the signature no longer matches.
• Signing with a different address from the one the funds come from. A Bitcoin wallet, for example, can manage several addresses.
• Sending the test transfer from an exchange: it proves nothing about your self-hosted wallet.
• Choosing another network than the one specified: the funds may be lost permanently.
• Depositing from a relative’s wallet: the proof must concern a wallet that belongs to you.
• Typing your recovery phrase on a site presented as a “verification”: it is an attempt at theft.

What a proof of ownership never requires

Proving that a wallet belongs to you never requires revealing what would let someone empty it. No legitimate provider needs your recovery phrase, your private key, your passwords or your two-factor authentication codes.

Scams play on exactly this confusion: a fake “compliance” message, a link to a page imitating your provider, a made-up deadline. Check that the provider appears in ESMA’s register, and always go through its own website or your customer area.