To make a cross-chain swap without a centralized exchange, you need a cross-chain swap interface that can coordinate the exchange between the source and destination blockchains.
For example, you may hold BTC on Bitcoin but want ETH on Ethereum, or hold ETH and want SOL on Solana. Instead of depositing the asset into a centralized exchange, trading it there, and withdrawing the result, a cross-chain swap can coordinate the exchange across supported blockchains.
The basic process is:
Choose the assets → get a quote → provide a receiving address → send the source asset → receive the destination asset
Here is how it works.
1. Choose What You Want to Swap
Start by selecting the cryptocurrency you have and the cryptocurrency you want to receive.
For example:
BTC on Bitcoin → ETH on Ethereum
Because these assets exist on separate blockchains, the swap needs cross-chain infrastructure capable of coordinating liquidity and settlement between the two networks.
A quote should show how much of the destination asset you are expected to receive, along with relevant fees, estimated completion time and any minimum-received protection.
2. Provide an Address for the Crypto You Want to Receive
You will need an address on the destination network to receive the resulting cryptocurrency.
If you are swapping BTC for ETH, for example, you need an Ethereum address capable of receiving ETH.
This means that even when a cross-chain swap does not require an account with a centralized exchange, you still need somewhere to hold the cryptocurrency you receive. This can be a self-custody wallet, hardware wallet or another compatible wallet provider that supports the destination asset and network.
Always verify that the receiving address is for the correct blockchain before initiating the swap.
3. Do You Need to Connect a Wallet?
Not necessarily.
Cross-chain swap interfaces can allow users to interact with the same onchain swap process through either a connected wallet or a deposit-address flow.
With a connected wallet, the wallet helps package the transaction details and allows the user to approve the transfer through the interface.
A walletless flow separates those steps. The swap interface provides the deposit details, and the user sends the required cryptocurrency to the generated address without connecting their wallet to the interface.
The swap itself still takes place onchain. Walletless simply means that the user’s wallet does not need to be connected to the swap interface.
A useful comparison is guest checkout in online shopping: you can complete the transaction without connecting an account to the interface.
You still need a wallet or compatible service to send the source cryptocurrency and an address where the destination cryptocurrency can be received.
4. Review the Quote
Before sending anything, review what the swap is expected to return.
The quote should make it clear:
- What asset and network you are sending
- What asset and network you are receiving
- Expected amount received
- Minimum amount received, if applicable
- Fees included in the quote
- Estimated completion time
- Receiving address
For users learning this process, allblu’s interactive how to swap guide walks through these stages using live quotes, showing how a cross-chain swap progresses from selecting assets and reviewing the quote through sending the source asset and receiving the destination asset.
5. Send the Source Cryptocurrency
Once the swap has been initiated, the source asset needs to be sent.
If a connected wallet is being used, the transaction can be submitted through the wallet.
With a walletless deposit flow, the interface instead provides the deposit information needed to make the transfer. The user can then send the cryptocurrency from their wallet or another service capable of making the withdrawal.
For example, a BTC to ETH swap may generate a Bitcoin deposit address. The user sends BTC to that address while providing an Ethereum address where the ETH should ultimately be received.
The incoming transaction is then detected onchain and processed according to the swap’s execution mechanism.
6. Receive the Destination Asset
Once the source transaction has been confirmed and the swap has executed, the destination asset is sent to the receiving address.
The exact mechanics behind this process differ between cross-chain systems. Liquidity may come from pools, liquidity providers, aggregators, intent-based systems, Just-in-Time liquidity or other execution models.
The important distinction for the user is the resulting asset and network.
For example:
BTC on Bitcoin → ETH on Ethereum
means the user sends BTC on its native network and receives ETH on Ethereum.
What Should You Check Before Making the Swap?
Before sending cryptocurrency, verify the source asset, destination asset, networks and receiving address.
It is also worth comparing the final amount expected to arrive, rather than looking only at an advertised fee percentage. Network fees, liquidity, execution costs, service fees and market conditions can all affect the final result.
A cross chain swap interface should clearly show the quote and destination details so the user understands what they are sending and what they are expected to receive.
Once the transaction has been submitted, blockchain transactions generally cannot be reversed, making it important to verify these details before sending the source asset.