A Uniswap crosschain swap exchanges tokens across two blockchain networks in one user flow. Instead of bridging an asset first and opening a second swap afterward, you choose the source token and network, the destination token and network, then review one combined route. This guide explains how the process works, which costs and networks to check, and what to do when the destination tokens do not arrive as expected.

Last reviewed: September 1, 2026. Supported networks, tokens, routes, fees and interface labels can change. Confirm the live quote in the official Uniswap app before approving a transaction. This independent guide is educational and is not financial advice.

What is a Uniswap crosschain swap?

A crosschain swap starts with one asset on a source blockchain and delivers another asset on a destination blockchain. For example, a user could exchange ETH on Ethereum for USDC on Base without manually completing a separate bridge transaction and then a same-network swap.

Uniswap combines the required steps into one route. Its current help documentation says the crosschain component is powered by Across, while Uniswap routing handles the swap logic. Across uses an intents-based system in which fillers deliver assets on the destination network and are reimbursed after the protocol verifies fulfillment.

The simpler interface does not turn two blockchains into one. The route still depends on smart contracts, liquidity, relayers or fillers, source-network confirmation and successful delivery on the destination chain.

Crosschain swap vs bridge vs regular swap

These actions solve different problems:

  • Regular swap: exchanges one token for another on the same network.
  • Bridge: moves an asset from one network to another, normally without intentionally changing the asset.
  • Crosschain swap: moves value between networks and can change the token as part of the same route.

If you want ETH on Ethereum to become ETH on Base, a bridge may be sufficient. If you want ETH on Ethereum to become USDC on Base, a crosschain swap can combine the network transfer and token exchange. Always read the proposed output carefully because similarly named assets can have different contract addresses or representations.

Which networks support Uniswap crosschain swaps?

As of this review, the Uniswap Help Center lists crosschain swaps on:

  • Ethereum;
  • Unichain;
  • Arbitrum;
  • Base;
  • Optimism;
  • Soneium;
  • ZKsync;
  • Zora;
  • World Chain.

Uniswap’s June 2026 product announcement also named Linea and MegaETH in its rollout list. However, the current Help Center list does not include them. Product availability can change or differ by route, token and application version, so treat a valid live quote in the official Uniswap interface as the final check for the transaction you intend to make.

Support for a network in Uniswap products does not automatically mean it supports crosschain swaps. The broader Uniswap network list includes chains that the crosschain feature may not route to or from. At the review date, the crosschain Help Center specifically lists Avalanche, Blast, BNB Chain, Celo, Monad, Polygon, Solana and X Layer as unavailable for this feature.

How to make a crosschain swap on Uniswap

1. Open the official Uniswap application

Navigate to the official Uniswap web app from a saved bookmark or use the verified Uniswap Wallet. Avoid sponsored search results, unsolicited messages and domains that imitate the brand. A legitimate swap never requires entering a seed phrase into a website.

2. Connect or select your wallet

Choose the account holding the source token. Check the full address if you use several wallets. The wallet must be able to sign on the source network and should hold any native token required for approval or network costs.

3. Select the source token and network

Choose the asset you want to spend and the blockchain where it currently exists. Verify the token contract instead of trusting its symbol alone. Scam tokens can reuse familiar names, and the same legitimate asset may have different contracts across networks.

4. Select the destination token and network

Choose the asset you want to receive and set a different supported destination network. When the two networks differ, Uniswap can look for an eligible crosschain route. If no quote appears, that token pair, amount or network direction may not be supported at that moment.

5. Enter the amount

Start with a modest amount when using a route for the first time. Do not select the entire balance of the native gas token without reviewing whether the wallet needs some of it to submit the source-side transaction. The available maximum can differ from the displayed total balance.

6. Review the complete quote

Before confirming, inspect:

  • source and destination networks;
  • both token contract addresses;
  • amount sent and estimated amount received;
  • minimum output or price-protection information;
  • estimated network and bridge costs;
  • route provider and expected completion time;
  • price impact and any warnings.

A convenient one-action flow can still contain several underlying stages. Compare the final amount received rather than evaluating only one fee line.

7. Approve the token if required

An ERC-20 token may require an approval before the swap can spend it. Approval is an on-chain permission, not the swap itself. Verify the spender, network and allowance in the wallet. Avoid accepting an unexpected unlimited approval simply to bypass a warning.

8. Confirm the crosschain swap

Read the wallet simulation and transaction details, then confirm only if they match the quote. Save the source transaction hash or order reference. Do not close the wallet permanently or submit the same swap again merely because delivery is not instant.

9. Track delivery on the destination network

Use Uniswap’s activity view for the combined status. If necessary, check the source transaction in the appropriate block explorer and the bridge progress in the Across explorer. Once complete, switch the wallet to the destination network and verify the received token contract.

What fees does a Uniswap crosschain swap include?

Uniswap states that its crosschain quote includes the Across bridging fee and applicable network costs. The Across fee supports the relayers or fillers and liquidity providers that deliver assets on the destination chain. Costs can change with the networks, amount, liquidity and current demand.

The economic cost can include more than a line labeled “fee”:

  • Source network cost: gas for an approval or transaction on the starting chain.
  • Bridge or filler fee: compensation reflected in the crosschain quote.
  • Swap liquidity cost: the effect of pool fees and available liquidity on the rate.
  • Price impact: a large trade can move through less favorable liquidity.
  • Destination action cost: later use of the received tokens may require the destination network’s native gas token.

According to Uniswap’s Across explanation, the displayed crosschain quote includes a fee paid to the relayers and liquidity providers powering Across, and neither Across Protocol nor Uniswap receives that particular fee. Fee structure can change, so use the live quote rather than a fixed percentage from an older article.

Do you need gas on both networks?

You generally need to satisfy the source-side wallet request, which may include an approval or transaction requiring the source network’s gas asset. Uniswap may bundle or account for other route costs in the quote, depending on how the transaction is executed.

Even if the crosschain swap delivers the destination token successfully, you may need the destination chain’s native gas token for a later transfer, approval or swap. Receiving USDC on Base, for example, does not automatically guarantee that the wallet has ETH on Base for a future independent transaction.

Do not send gas tokens to a network based solely on their symbol. ETH on Ethereum and ETH on Base are balances on different chains.

How long does a Uniswap crosschain swap take?

Uniswap says most crosschain swaps complete within a few minutes, although some can take longer. Timing depends on source-network confirmation, destination liquidity, filler availability, route complexity and network conditions.

A longer wait is not automatically a loss. First check whether the transaction is waiting for source confirmation, bridge fulfillment or a final destination-side step. Repeating the transaction can create two swaps if the original route completes later.

Why is my Uniswap crosschain swap delayed?

Common explanations include:

  • the source transaction has not confirmed;
  • network congestion has slowed processing;
  • the Across bridging step is still being fulfilled;
  • a destination swap or delivery step is pending;
  • the wallet is showing the wrong network;
  • the received token is not automatically displayed;
  • the transaction failed at an intermediate step and requires a retry.

Open the activity details before taking action. Uniswap’s troubleshooting guidance says an intermediate failure can prompt the user to retry from the failed step instead of restarting the entire process.

What to do when destination tokens are not showing

  1. Check the combined status. Open the transaction in Uniswap activity and determine whether it is pending, completed or failed.
  2. Verify the source transaction. Use the source chain’s block explorer to confirm that it succeeded.
  3. Check Across progress. Use the official Across explorer when the bridging stage needs closer inspection.
  4. Switch to the destination network. Wallets display balances by chain.
  5. Verify the token contract. Add the correct destination token manually if the wallet does not list it.
  6. Allow additional processing time. A source success does not always mean every later stage is final.
  7. Use the offered retry flow. If Uniswap identifies a failed intermediate step, retry that step rather than creating a duplicate swap.
  8. Contact official support when necessary. Provide public transaction hashes and route details, never a private key or recovery phrase.

Why a crosschain quote may be unavailable

No quote can mean that the selected network is unsupported, the token cannot use the route, liquidity is insufficient, the amount falls outside available limits or the service is temporarily unable to calculate a safe route. Try confirming the exact token contracts and reducing the amount, but do not break a transaction into pieces without considering the extra fees and price impact.

When crosschain swapping is unavailable, Uniswap may still support manual bridging followed by a regular swap. That alternative introduces separate confirmations, quotes and signing steps. Compare the final expected output and risk rather than assuming the longer route is automatically cheaper.

Crosschain swap security checklist

  • Use only the official Uniswap app or verified wallet.
  • Confirm the source and destination networks independently.
  • Verify token contracts on both chains.
  • Review the final output, not only the headline exchange rate.
  • Inspect every approval and avoid unexplained permissions.
  • Start with a small amount on an unfamiliar route.
  • Preserve transaction hashes until delivery is verified.
  • Use official block explorers and the official Across explorer.
  • Never provide a recovery phrase to “release” a delayed transfer.
  • Remember that bridge and smart-contract risk cannot be eliminated.

Frequently asked questions

Can Uniswap swap tokens between different networks?

Yes. For supported tokens and network routes, Uniswap crosschain swaps combine bridging and swapping into one user flow through Uniswap routing and Across.

Is a Uniswap crosschain swap the same as bridging?

No. Bridging normally moves an asset to another network, while a crosschain swap can deliver a different token on the destination network.

Why is my Uniswap crosschain swap not received?

The source transaction, Across fulfillment or destination delivery may still be processing. Check Uniswap activity, the relevant block explorer, the Across explorer and the selected destination network before retrying.

How long should a Uniswap crosschain swap take?

Uniswap says most complete within a few minutes, but congestion, route conditions and intermediate steps can make some transfers take longer.

Does Uniswap charge a crosschain fee?

The quote includes applicable network costs and the Across bridging fee. The complete cost also depends on liquidity, price impact and any required token approval.

Can I crosschain swap from Polygon or Solana?

At the review date, Uniswap’s dedicated crosschain Help Center lists Polygon and Solana as unavailable for crosschain swaps, even though Uniswap products support other activity on those networks. Check the live interface because availability can change.

What happens if one step fails?

Uniswap says the interface can prompt you to retry from the failed intermediate step rather than restarting from the beginning. Review the activity record before submitting anything new.

Final takeaway

A Uniswap crosschain swap can replace a manual bridge-and-swap sequence with one coordinated route, but it still crosses distinct networks and depends on approvals, liquidity, fillers and smart contracts. Check live network support, compare the final amount received and keep the transaction identifiers until the destination balance is confirmed.

For current details, consult Uniswap’s official explanations of crosschain swaps and supported networks, crosschain troubleshooting, and the Across bridge integration.

Open Uniswap ↗Official website