Vote as and SPO

Step 1: Hot environment queries

1st Query

Query the governance state where you will get the governance action ID you need to build your offline vote file

cardano-cli conway query gov-state \
--mainnet \
--out-file gov-state.json

2nd Query

Query the UTXO of the payment address you plan to use for the vote transaction (ideally one for which you have the signing keys stored in your cold environment).

cardano-cli conway query utxo \
--mainnet \
--address <YOUR WALLET ADDRESS> \
--out-file wallet-utxo.json

3rd Query

Query the protocol parameters from your online environment so you can use them later to calculate the transaction fee in your cold environment.

cardano-cli conway query protocol-parameters \
--mainnet \
--out-file pparams.json

Step 2: Transfer All Files to Cold Environment

Transfer these three files(gov-state.json, wallet-utxo.json, pparams.json) to your cold environment to securely build the vote file, construct the transaction, and perform the signing process offline. This minimizes exposure to potential online threats during the transaction.

Locate the UpdateCommittee Proposal and Extract the Governance Action ID

Scroll to the bottom of the gov-state.jsonfile in your cold environment, locate the proposal labeled UpdateCommittee, and copy the governance action ID.

Step 3: Build the vote file

Build your vote file with your chosen vote and optional rationale. If including a rationale feels too complex, you can omit the --anchor-url and --anchor-data-hash parameters.

cardano-cli conway governance vote create \
--yes \
--governance-action-tx-id 47a0e7a4f9383b1afc2192b23b41824d65ac978d7741aca61fc1fa16833d1111 \
--governance-action-index 0 \
--anchor-url <YOUR RATIONAL URL LINK> \  #Providing a rationale is optional
--anchor-data-hash <YOUR RATIONAL HASH> \ #Providing a rationale is optional
--cold-verification-key-file cold.vkey \
--out-file action.vote

Retrieve UTXO from wallet-utxo.json for Transaction Input

Open your wallet-utxo.json file in your cold environment and identify a suitable UTXO to use as the transaction input. You'll need the transaction hash and index (txHash#index) for the next steps.

Step 4: Build Transaction Draft

We build a draft transaction first because the exact fee isn't known yet. To calculate the correct fee, we need to estimate it based on a nearly complete transaction. By using available inputs to create a draft, we can then calculate the fee and adjust the final transaction outputs accordingly.

cardano-cli conway transaction build-raw \
--tx-in <YOUR WALLET UTXO> \
--tx-out <YOUR WALLET ADDRESS>+0 \
--vote-file action.vote \
--fee 0 \
--out-file tx.raw

Step 5: Calculate the transaction fee

Provide the protocol parameters file pparams.json and set --witness-count to the number of keys you'll use to sign (your pool cold key and wallet payment key); set both --tx-in-count and --tx-out-count to 1, since you're using one input and sending the change back to yourself as a single output.

cardano-cli conway transaction calculate-min-fee \
--tx-body-file tx.raw \
--protocol-params-file pparams.json \
--witness-count 2 \
--mainnet \
--tx-in-count 1 \
--tx-out-count 1

You should get an output like this:

Step 6: Build the Final Transaction

Now that you have the transaction fee, determine the amount of lovelace to include in your output by subtracting the fee from the total value of the wallet UTXO you're spending. Use this result as the output amount in your final transaction body file.

expr 86843345 - 171529

cardano-cli conway transaction build-raw \
--tx-in 207b226e110e13bb18b119fcd313520e0fcd060b2bc9fb9a5e5bc6e94ab10f3b#0 \
--tx-out addr1vyae679fqna7yal7qhw6trxdd06k78ynt70qejyyw96ev3qz0m3hh+86671816 \
--vote-file action.vote \
--fee 171529 \
--out-file tx.raw

Warning If your transaction draft becomes larger in size after calculating the fee — for example, because the new output values added more bytes to the file — you must re-run the calculate-min-fee command to check whether the required fee has changed. If the fee has increased, update your output value accordingly and verify the transaction again. A larger transaction file requires a higher fee, so always double-check after making changes.

Step 7: Sign the transaction

Sign your transaction body file using both cold.skey and payment.skey

cardano-cli conway transaction sign \
--tx-body-file tx.raw \
--mainnet \
--signing-key-file payment.skey \
--signing-key-file cold.skey \
--out-file tx.signed

Step 8: Move the Signed Transaction to the Hot Environment

Move the signed transaction file to your hot (online) environment to submit it to the blockchain. This file does not contain any sensitive private key data — it only includes the transaction details and cryptographic witnesses required for validation, making it safe to transfer across environments.

cardano-cli conway transaction submit \
--mainnet \
--tx-file tx.signed

And voilà — congratulations! You've successfully cast your vote as a Stake Pool Operator in our governance system. If everything went well, you should see an output like this: