How Optimism Processes Transactions on Ethereum
Optimism runs transactions on its own chain and settles them on Ethereum. A sequencer confirms them fast, and gas is paid in ETH on OP Mainnet, not OP.
Vahe HakobyanEditor-in-chief
Updated Oct 6, 20263 min readFact-checked
On this page
- You need a wallet that supports Optimism and ETH for gas.
- The OP token is for governance, not gas on OP Mainnet.
- A fast Optimism confirmation is not Ethereum finality.
- The IRS treats crypto as property, so trades and payments can be taxable.
When you send a transaction on Optimism, your wallet, the sequencer, and Ethereum each play a part. This guide covers what you need before you start, the steps the transaction follows, and the records to keep.
What do you need before you start?
Optimism is an Ethereum Layer 2, so your wallet must support it. You need ETH on Optimism for gas; if your ETH is on Ethereum, move some to Optimism first.
How does Optimism process your transaction?
Once your wallet is ready, you start the send flow. A sequencer orders and executes transactions on the Optimism chain, then Optimism posts data to Ethereum.
- 1Choose Optimism and enter detailsSelect Optimism, then enter the address and amount.
- 2Review the gas feeCheck the gas estimate in ETH; OP does not pay gas.
- 3Sign the transactionYour signature authorizes the transfer and sends it to the sequencer.
- 4Let the sequencer executeThe sequencer orders and runs the transaction, then confirms it fast.
- 5Watch for Ethereum settlementOptimism posts batch data to Ethereum; finality follows the challenge window.
What should you do after the transaction?
After confirmation, save the transaction details. You need them for tracking and US taxes, and you should watch for fake support messages.
- Save the transaction hash, date, and amount.
- Record the US dollar value for tax basis.
- The IRS treats crypto as property, so a trade or payment can be taxable.
- Support staff do not ask for your seed phrase or private keys.
Frequently asked questions
Optimism runs its own chain, but it is an Ethereum Layer 2. It posts data to Ethereum and inherits Ethereum security.
No. Gas on OP Mainnet is paid in ETH. The OP token is for governance.
The sequencer confirms fast on the Optimism chain. Ethereum finality comes later, after the batch is posted.
The state does not change, but you usually still pay gas. Your wallet shows the failure, and a support agent cannot reverse it.
