A Checklist Before You Sign a Crypto Transaction

Signing is the moment a transaction becomes real. Once a signed transaction is broadcast, the network treats it as final, and there is no one who can reverse it for you. That is why the few minutes before you sign matter more than anything that comes after.

This Security piece is the checklist we recommend running before every signature. We use XColdPro, our air-gapped cold wallet software for Windows and macOS, as the worked example, but the habits apply to any wallet you use.

1. Make sure the request is really yours

Start with where the transaction came from. A payment you planned yourself is very different from one you were asked to make in a message, a pop-up or a call.

• Be cautious with urgency. Requests to move funds "now", to "verify" a wallet or to "fix" an account are common pressure tactics.
• Confirm a new payment address through a second channel you already trust, not through the same message that delivered it.
• No transaction you sign ever needs your seed phrase. No legitimate wallet, company or support agent ever needs your seed, and no one at XColdPro will ask for it. If a step asks you to type or share it, stop.

2. Go offline before you build the transaction

With XColdPro, the signing computer should have no network path while keys are in use. Our How It Works page sets out the order: disconnect the computer from every network, then create the transaction with the destination, amount and fee.

Before you continue, check that WiFi, Bluetooth and Ethernet are actually off on the machine you are using. Severing those paths is what removes the remote attack surface, so it is worth confirming rather than assuming.

3. Check the network

Many assets and address formats look alike across chains. Before you sign, confirm that the network selected in your wallet is the network the recipient expects to receive on. XColdPro supports 22 networks from a single installation, and keeps keys isolated by chain, so selecting the right one is part of every transfer.

If the recipient has not told you which network to use, ask before sending. A correct address on the wrong network is still a mistake.

4. Verify the recipient address in full

The address is the detail most worth slowing down for. Copy-and-paste errors, altered clipboard contents and look-alike addresses that share the first and last few characters with one you have used before are all ways a payment can go to the wrong place.

• Compare the whole address, not just the beginning and the end.
• Avoid copying an address from your transaction history; use the address from the source you verified in step 1.
• Cross-check the address by QR code where possible. On our How It Works page this is part of the signing step: check every detail, cross-checking the address by QR code, and sign while still offline.

5. Check the amount and the fee

Read the amount on the screen of the device that is about to sign, digit by digit, including the decimal places. Then look at the fee. A fee that seems far higher than usual is a reason to pause and recheck the transaction before going further.

If the amount is large or the recipient is new, consider sending a small test transfer first and confirming that it arrives before you send the rest.

6. Sign while still offline

Only when every detail matches should you approve the signature. With XColdPro, signing happens on the air-gapped computer, with keys generated and used only while it is offline. Only the signed transaction ever reaches the network.

7. Reconnect only to broadcast

Once the transaction is signed, reconnect only to broadcast it. Afterwards, check that the transaction appears on the network with the recipient and amount you approved.

8. If several people approve, each one checks

For shared funds, the checklist applies to every cosigner, not only the person who prepared the transaction. With Citadel, XColdPro's M-of-N approval, each cosigner signs a digest of the exact transaction on their own device. Finalisation verifies every signature, so changing the recipient, the amount or the threshold invalidates the approvals already collected.

That protection works best when each cosigner actually reads the recipient and amount before approving. The threshold is enforced by XColdPro on your own devices, and anyone holding the seed can still spend outside XColdPro, so treat Citadel as governance over how funds move and keep the seed protected as well.

The checklist

• I planned this payment, or confirmed the request through a channel I trust.
• No step asked for my seed phrase.
• The signing computer is disconnected from every network.
• The selected network matches what the recipient expects.
• The full recipient address matches, cross-checked by QR code where possible.
• The amount and the fee are what I intended.
• I signed offline and reconnected only to broadcast.
• Every cosigner checked the details before approving, if more than one person signs.

Cold storage is a set of controls, not an absolute. A short, repeatable routine before each signature is one of the most effective of those controls, and it costs only a few minutes.

FAQ

Can a signed transaction be cancelled?
Once it has been broadcast, you should treat it as final. That is why the checks in this list happen before you sign, not after.

Do I need to run the full checklist for small amounts?
Running it every time is what turns it into a habit. The steps take only a few minutes, and the address and network checks matter whatever the amount.

What should I never share while sending a transaction?
Your seed phrase and your private keys. No legitimate wallet, company or support agent ever needs your seed.

This article is general information about using a self-custody wallet. It is not financial or legal advice.