Offline transactions

Is below possible.

  1. Connect the Trezor to Suite software on a laptop in airplane mode (no network)
  2. Put in a transfer for some BTC to another wallet
  3. Remove the Trezor and turn off the laptop
  4. At some later point open the laptop (without the Trezor), give it network so the transfer is activated

Hi @Urtamos,

This cannot be done directly as you explained in your steps. However, it can be done by disabling the “broadcast” feature (by exporting “raw data” and broadcasting the data later).

First, I would like to mention that for creating and signing a raw transaction in Trezor Suite, you need to be online. However, you do not need to send the transaction from the same network if you don’t want to. Simply put, you can save the raw transaction and send it later from a different network.

Sending a raw transaction simply means broadcasting a transaction that has already been created and signed. This can be used with any transaction data that has been generated and signed but not broadcast, including Locktime and OP_Return transactions.

Creating and broadcasting raw transactions (when you are not connected to any network)

To create raw transaction data:

  1. Create a new transaction with Broadcast set to off.
  2. Click on Sign.
  3. Review all details on your Trezor and confirm that they are correct.
  4. Copy the signed transaction data or save it as a text document. Close the window.

To send raw transaction data you need to use a service that allows it, you can use for example our blockchain explorer (option “Send Transaction” from the bottom of the page)

Or you can use Trezor Suite:

  1. Select Send Raw from the “three dots” drop-down menu.

  1. Paste the raw transaction data into the text box.
  2. Click Send.
  3. The transaction will be broadcast and a confirmation will appear on screen.

Thanks for the info. Hmmm, so how “safe” is this raw data? What if the computer is compromised, can the raw data be altered so the BTC is transferred to some other destination?

It is safe. The raw data contains information about all the specifics of the transaction (destination address, amount, fee, …)

You can use it even on a compromised computer. If for example the destination address is changed, the signature is changed and it cannot be used anymore.