An atomic swap exchanges one asset for another between two parties on different blockchains, and it is designed so that either both sides complete or neither does, provided each party acts within the time limits. A bridge moves an asset or its representation from one blockchain to another. A swap needs a counterparty that wants the other side of the trade, while a bridge transfer does not.
Last updated: September 25, 2026.
How does an atomic swap work?
Each party locks its asset in a contract on its own network. The contracts typically use a hash lock and a time lock. The party who created a secret claims the other asset by revealing it, and the revealed secret lets the second party claim in turn. If the secret is never revealed before the time limits, each party can reclaim its own asset.
Because of this design, both networks need to support the required locking logic, and both parties need to act before the time limits expire. The time limits are staggered so that the second party has time to claim after the secret appears.
How does a bridge transfer work?
A bridge transfer starts on the source network and completes on the destination network. A message or proof about the source transaction is verified, and the destination side releases or mints the asset. The holder keeps the same asset, or a representation of it, in a new location.
LayerZero's cross-chain messaging sends that instruction between contracts, and decentralized verifier networks verify it. The OFT standard applies this model to token transfers.
What are the main differences?
| Question | Atomic swap | Bridge transfer |
|---|---|---|
| What does the holder receive? | A different asset from the counterparty | The same asset, or a representation of it |
| Is a counterparty needed? | Yes, one that wants the other side | No trading counterparty |
| What completes the operation? | Both parties claiming before time limits | Verification of the source transaction, then execution on the destination |
| What must the networks support? | Compatible hash and time locks on both sides | The bridge's contracts on both sides |
The two answer different needs. A swap changes which asset a party holds. A transfer changes where it is held. The cross-chain transfers vs swaps overview explains how some routes combine both.
FAQ
Is an atomic swap a type of bridge?
No. An atomic swap does not move an asset between networks. Each asset stays on its own network and changes owner.
What limits atomic swaps?
They need a matching counterparty and a compatible locking design on both networks, and each party must act within the time limits. A bridge transfer does not depend on finding a direct counterparty.
Which blockchains support atomic swaps?
Any pair of networks that both support hash locks and time locks, either in their scripting language or through smart contracts. Networks without that support can use other cryptographic techniques, which work differently.
What should I check before using a bridge?
Two useful starting points are which asset arrives on the destination and how the transfer is verified. The cross-chain bridge security overview explains the verification side.
Choose by the outcome
For cross-chain transfer concepts and supported integration paths, start with the LayerZero developer resources.