Electrum

We've noticed that different wallet versions can behave a bit differently. If you’re using a version before v4.5.4, make sure to use the older format accordingly.

This tutorial uses Electrum version 4.6 as an example.

1. Open Electrum Wallet, go to the Send tab.

2. In “Pay to”, Please enter the zkBTC Bridge Mainnet Operator address, the amount (≥ 21,000 sats) and OP_RETURN ouput:

3. Then, proceed with the cross-chain transfer following the steps below. Just make sure to check your wallet version first.

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> Format (pre-4.5.4):

zkBTC Operator Address, amount
OP_RETURN [your Ethereum address without "0x"], 0

example:

bc1qcwc08898aseahq2e5920m9395py3jjtm2xnt0s90slqra7cry2dq2xv9uq,0.00021
OP_RETURN a94f5374fce5edbc8e2a8697c15331677e6ebf0b,0

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> Format (Version 4.5.4 and above):

zkBTC Operator Address, amount
script(OP_RETURN your_Ethereum_receiving_address_without_0x_prefix),0

example ( based on Electrum version 4.6.0)

bc1qcwc08898aseahq2e5920m9395py3jjtm2xnt0s90slqra7cry2dq2xv9uq,0.00021
script(OP_RETURN a94f5374fce5edbc8e2a8697c15331677e6ebf0b),0

⚠️ Description: zkBTC Operator address: bc1qcwc08898aseahq2e5920m9395py3jjtm2xnt0s90slqra7cry2dq2xv9uq

Amount: 21,000 sats

OP_RETURN data:format: script(OP_RETURN Your Ethereum receiving address, without 0x prefix)

0: OP_RETURN output amount is 0 ( for data only)

⚠️ Note:

• Amounts no less than 21,000 sats, or it will fail.

• Double-check all fields and broadcast the transaction.