How to Bridge to Optimism With Across Bridge

Across Bridge helps you move funds to Optimism without treating bridging like a guessing game, and Across Bridge is built for fast cross-chain transfers filled by relayers.

The problem is usually practical: your funds are on Ethereum, Arbitrum, Base, Polygon, zkSync, or another supported chain, but the app you want to use is on Optimism. You need the right token on the right destination chain, with a clear view of fees and fewer chances to click the wrong thing.

This guide focuses on that exact move: bridging to Optimism. It is not a deep token thesis, a swap tutorial, or a tour of every L2. It is a careful walkthrough for getting funds onto Optimism with Across.

What You'll Need

Have these ready before you start:

A non-custodial wallet such as MetaMask.
Funds on the source chain you want to bridge from.
Optimism selected as the destination chain.
A little crypto for gas on the source chain.
Enough time to review the token, route, received amount, and wallet prompts.

Bridging is not the same as swapping. A swap changes one asset into another. A cross-chain bridge moves value from one chain environment to another. Across is an intents-based bridge, not a swap AMM, so your main job is to define the transfer you want and check that the quoted route matches it.

Step 1: Connect Your Wallet

Connect the wallet that holds the funds you want to move. MetaMask is a common choice, but the same basic checks apply to other compatible wallets.

Confirm the address shown in the bridge interface. If you use multiple wallets, this small check matters. A balance can look missing simply because you connected the wrong address or are viewing the wrong network.

Step 2: Choose the Source Chain and Optimism

Pick the chain where your funds currently sit as the source chain. Then choose Optimism as the destination chain.

Do not treat all L2s as interchangeable. Optimism, Base, Arbitrum, Polygon, zkSync, and Ethereum are separate networks. If the app or wallet balance you need is on Optimism, the destination must be Optimism. Choosing a different chain because it looks familiar can create extra work or leave funds somewhere you did not intend.

Step 3: Select the Token and Amount

Choose the token you want to bridge, then enter the amount. Leave enough behind for gas if you may still need to act on the source chain.

Now read the quote. Look at the bridge fee, source-chain gas, and estimated received amount. The exact cost can change with route, liquidity, and network conditions, so do not assume a fixed fee or a guaranteed transfer time. If you are moving a small amount, fees can matter more than they first appear.

Step 4: Understand How Across Bridge Fills the Transfer

Here is the simple version: you deposit on the source chain, a relayer quickly fills your request on Optimism, and the relayer is later reimbursed after optimistic settlement. That is why transfers can feel fast.

This is different from a basic lock-and-mint or canonical bridge flow. Across uses relayers and available liquidity to complete the destination-side fill, while settlement happens afterward. You do not need to manage that process manually, but understanding it helps you know what the bridge is actually doing.

For the actual route, use Across Bridge, set Optimism as the destination, and compare the token, chain, fee, and received amount before you sign.

Step 5: Approve the Token if Needed

Some ERC-20 tokens require an approval before the bridge transaction can use them. If your wallet asks for approval, check that the token and chain match the bridge action you are taking.

If a prompt shows an unexpected token, contract, chain, or permission, stop and review the page. Token approvals are normal, but they still deserve attention because they authorize spending behavior from your wallet.

Step 6: Confirm the Bridge Transaction

After any required approval, confirm the bridge transfer. This starts the movement from your source chain toward Optimism.

Watch the status, but avoid panic-refreshing or sending duplicate transfers just because a wallet display is slow. Network conditions, relayer activity, and settlement mechanics can affect what you see while the transfer is being filled.

When the transfer completes, switch your wallet to Optimism and check the balance. If the token does not appear automatically, you may need to add the token display in your wallet. Make sure you are viewing the same address on the Optimism network.

Common Mistakes That Cost People Money

The biggest mistake is choosing the wrong destination chain. Optimism is not Base, Arbitrum, Polygon, Ethereum, or zkSync. Similar wallet addresses do not mean the same network.

Another common mistake is selecting the wrong token. Token symbols can look familiar across chains, but support and liquidity can differ. Confirm the asset before approving anything.

Fees are also easy to underestimate. You may pay source-chain gas, a bridge fee, and later need gas on Optimism for the next transaction. Read the quote as a real cost, not a decorative number.

Be careful with unofficial front-ends. Use the bridge interface you intended to use, avoid random links in direct messages, and do not sign wallet prompts that do not match the action on the page.

Finally, bridges have risk. Smart-contract risk, wrong-chain mistakes, fee changes, and user error are real. Across is designed for fast intents-based bridging, but no bridge should be treated as risk-free.

A Note on ACX

ACX is the Across token. You do not need to bridge ACX unless ACX itself is the asset you want on Optimism. For a normal bridge-to-Optimism workflow, focus on the chain route, the token you need, the quote, and the wallet prompts.

That distinction matters for beginners. Using a bridge does not automatically mean buying or moving the bridge's token.

Bridge to Optimism With a Clean Checklist

A good transfer is simple: connect the right wallet, choose the real source chain, set Optimism as the destination, select the correct token, review fees, approve only what matches, then check your funds on Optimism.

When you are ready to move, open Across Bridge, keep the destination set to Optimism, and read every wallet prompt before confirming.