How to transfer bitcoin from Bitcoin Core to Trezor hardware wallet

[rv79]

Hi all,

I should have some bitcoin from years ago on Bitcoin Core that I'm currently downloading (it's taking weeks). I bought a Trezor T hardware wallet and once I sync up Bitcoin Core, I would like to transfer over to Trezor. Also, my wallet.dat file with that bitcoin is currently offline on a USB and I will load it only once it's fully synced and will try to do it offline.
I came across this thread from years ago and it seems like this guy was trying to do the same thing as me and he got this answer. Is this still correct? Can anyone please confirm? Thank you.




Ok... so at this point I would probably do something like the following:

1. Setup TREZOR as required (if you want to use Electrum, go for it) and generate a receiving address.
2. Install and Setup Bitcoin Core. DO NOT use your old wallet.dat at the moment, just create a "dummy" wallet. At this stage I'd also recommend setting the Display Units to "BTC" just to avoid any confusion later (Settings -> Options -> Display -> Units to show amounts in)
3. Run Bitcoin Core and let it sync up to at least when you stopped using your wallet (ie. Let it sync until say 2012 or 2013 just to be safe if you think you stopped 6 years ago). This actually shouldn't take very long.
4. Shut down Bitcoin Core
5. Disconnect from ALL networks
6. Make a copy of your wallet.dat from the USB and put it in the Bitcoin Core datadir (By default, on windows this should be %appdata%\Bitcoin unless you changed it during install/setup), overwriting the default wallet.dat that would have been created during install/setup.
7. Start Bitcoin Core. It will likely need to spend a few minutes rescanning (but not redownloading) the blockchain for the transactions for your wallet. Once complete, you should be able to see all your coins, addresses and transaction history etc.
8. Once you can see all your coins, you can create a "test" transaction that sends a small amount of coins to your new TREZOR. Be mindful not to send "dust" Wink
9. Re-connect to the internet to broadcast the transaction and then disconnect again. (see notes below for alternatives)
10. Once you are satisfied that the TREZOR is working as it should be with your "test" transaction, you can then create a transaction that sends ALL your coins to your TREZOR (either the address from Step #1 or create a new TREZOR address). (see below)
11. Re-connect to the internet and send the transaction. (see below)


NOTES:
- Please note that the above is just what I would do, if I was in your situation. I don't necessarily recommend that you follow the same procedure.

- Step 7, If you don't see your coins or any transaction history, you'll need to check the wallet addresses and see if they still hold coins. ("File -> Receiving Addresses") and check some of the addresses on a block explorer like blockchain.info. Once you find the addresses with coins, make sure that you have sync'd Core up to the last date that these addresses have transactions listed for them.

- Step 8, I would recommend that you send at least 0.001 BTC as a test and don't send anything smaller.

- Step 9 and Step 11, if you'd rather not reconnect the computer with your wallet.dat on it to the internet, you can simply copy the "raw" transaction onto a USB, transfer it to another computer and broadcast using one the websites listed below. These websites can't do anything "bad" with your already signed transaction, it is no different to broadcasting the transaction to the network yourself. Smiley

To get the raw transaction, simply right-click on the new "unconfirmed" transaction in the "Transactions" tab, and select "copy raw transaction". Then paste that data into a text document (it will just be a big long "hex" string of numbers/characters), save the text file onto a USB and transfer to another computer.

Then on the online computer, copy the hex from the text document and paste into one of the following:
https://coinb.in/#broadcast
http://blockr.io/tx/push
https://live.blockcypher.com/btc/pushtx/
https://btc.com/tools/tx/publish

Several of these sites give you the option to "decode" or "verify" so you can double check the transaction details (output address, amount and fee etc) before broadcasting.


- Step 10, I would recommend that you switch on "Enable Coin Control Features" and "Spend unconfirmed Change" in Settings (Settings -> Options -> Wallet). Especially if you sent a test transaction, as you'll no doubt end up with "change" from that test and as your Core won't be sync'd, any change from the test won't be "confirmed" until you let Core sync all the way!

When you got to setup the transaction, on the "Send" tab, click the "Inputs" button and then the "Select All" button. You should be able to see the "bytes" value. This will also enable you to work out an appropriate fee. These websites will give you an idea of the fees currently in use:
https://btc.com/stats/unconfirmed-tx
https://bitcoinfees.21.co/

Please note that if you fail to use a "proper" fee, there is a good chance that your transaction (and all your coins) could get "stuck" in an unconfirmed state. I would highly recommend that you let Bitcoin Core calculate a fee for you (Use "Recommended" setting in the "Send" tab and use the slider to adjust to an amount/confirmation time that you are comfortable with)... unless you are 110% sure you know what you're doing setting a custom fee.

[1714833325]

1714833325

[ranochigo]

It sounds about right.

One thing that I would do differently from steps 9 and 10 (and actually clarified in the notes) would be to not reconnect your computer after you have transferred your wallet.dat over and use the raw transaction method. Note that for partial synchronization to work, you'll have to be sure of the exact timeframe whereby you have received the Bitcoins and to synchronize after that. Any transactions done beyond that synchronization would not be shown and there is a risk that Bitcoin Core accidentally creates an invalid transaction, which is fine just a bit annoying; it wouldn't cause you to lose your funds.

[o_e_l_e_o]

Please note that if you fail to use a "proper" fee, there is a good chance that your transaction (and all your coins) could get "stuck" in an unconfirmed state.

Coins can't get "stuck" in an unconfirmed state indefinitely. The transaction will either confirm or it will be dropped from the mempool, at which point you can make a fresh transaction with the same coins at a higher fee. Be aware that fees are the moment are very high thanks in part to the constantly increasing price. You are looking at spending upwards of 140 sats/vbyte to have a reasonably fast confirmation. This will eat up probably around one third of your 0.001 BTC "test" transaction in fees alone, and if you have a lot of inputs to move then you will end up paying a significant amount in fees.

If you are in no particularly hurry (and it doesn't sound like you are since you are happy to wait weeks for Bitcoin Core to sync), then I would just sit tight for the time being and wait until average fees have dropped by 90% or so.

[Lucius]

Wouldn't it be much easier and faster for OP if he made a dump of his private keys from Bitcoin Core and then import those keys into Electrum and from there is easy to move coins to Trezor?

Of course, this process is not without risks - the computer should be clean of malware/virus, and Electrum should be verified before installation. What is certainly not in dispute is that the whole procedure would not have to take weeks, but could be done within a maximum of 60 minutes.

[HCP]

Ok... so at this point I would probably do something like the following:
...snip...

I thought I recognised some of the idiosyncrasies in that text... https://bitcointalk.org/index.php?topic=2019233.msg20161692#msg20161692


I'm not entirely sure all of that convoluted stuff is necessary if you simply want to get your coins from an old Bitcoin Core wallet into your Hardware Wallet. At the very least, you simply need to create a transaction that sends the entire balance from Bitcoin Core to a receiving address from your Trezor.

Reading it now, it looks terribly complicated for what should be a simple operation.

Is there a reason you don't want to just sync Bitcoin Core, open (a copy of) your wallet.dat in the synced Bitcoin Core, let Bitcoin Core "rescan" the wallet, then send the balance to Trezor T? Is the wallet.dat not password protected or something?

[ranochigo]

Wouldn't it be much easier and faster for OP if he made a dump of his private keys from Bitcoin Core and then import those keys into Electrum and from there is easy to move coins to Trezor?

Of course, this process is not without risks - the computer should be clean of malware/virus, and Electrum should be verified before installation. What is certainly not in dispute is that the whole procedure would not have to take weeks, but could be done within a maximum of 60 minutes.

I really cannot recommend anyone trying to dumpwallet and importing everything into Electrum. Sure, it could be faster but at the expense of privacy.

If the wallet.dat is from a pretty old backup, you'll probably be looking to import tons of keys if OP is a heavy user or more addresses were generated after that backup. If you want to be sure, synchronizing Bitcoin Core is the only way, not to mention that it is difficult to import a huge list of addresses. My older computer took a day to synchronize and my newer one with NVMe took 4 hours. It will certainly not take weeks and that is the only way to be sure that it is empty.

Nevermind missed out on this:

I should have some bitcoin from years ago on Bitcoin Core that I'm currently downloading (it's taking weeks).

[Lucius]

It will certainly not take weeks and that is the only way to be sure that it is empty.

I should have some bitcoin from years ago on Bitcoin Core that I'm currently downloading (it's taking weeks).

In the case of OP, this process obviously takes much longer - an old computer and a slow internet connection are not an ideal combination for downloading more than 300 GB of data - so although I agree that it is much safer to make one transaction and send everything to HW, in case all BTC is located at several addresses it would be much easier just to dump a few private keys and import them to Electrum. However, if the OP is not 100% sure that he can do it in a completely correct and safe way, let him go a longer and safer way.