Earn uses Circle's CCTP v2 when a deposit, rebalance, or close needs to move USDC between supported chains. CCTP burns USDC on the source chain and mints the equivalent amount on the destination chain without a third-party custodian holding the funds.
- CCTP v2 moves USDC. Cross-chain deposits, rebalances, and closes use Circle's burn-and-mint flow.
- Four stages complete a move. Earn burns the source USDC, waits for attestation, mints on the destination chain, and deposits into the destination vault.
- Attestation controls most of the wait. Worst-case timing is approximately 19 minutes on Ethereum, Optimism, Arbitrum, Base, and Unichain; 8 minutes on Polygon; and 5 seconds on Monad.
- Closes return funds to your wallet. A cross-chain close skips the destination-vault deposit.
The four steps
- Burn
Earn redeems the source-vault shares to USDC and burns that USDC on the source chain.
- Attestation
Earn waits for Circle's Iris API to attest the burn. This is normally the longest stage.
- Mint
Earn submits the attestation on the destination chain, where CCTP mints the equivalent USDC.
- Deposit
The minted USDC is deposited into the destination vault in the same transaction, and the position begins earning.
Cross-chain closes skip the deposit stage: the minted USDC goes directly to your wallet.
For deposits and rebalances, the selected destination vault may become full or hidden while the bridge is in progress. If it can no longer accept the funds, Earn deposits into the next-best vault that your wallet has approved.
If the mint transaction reverts, the on-chain burn message and Circle attestation remain replayable. The funds are not held in escrow.
Supported chains and timing
Worst-case attestation time varies by chain:
| Chain | Worst-case attestation |
|---|---|
| Ethereum | ~19 minutes |
| Optimism | ~19 minutes |
| Arbitrum | ~19 minutes |
| Base | ~19 minutes |
| Polygon | ~8 minutes |
| Unichain | ~19 minutes |
| Monad | ~5 seconds |
The values above are worst-case attestation times. Earn checks for new attestations approximately every minute, so even a fast attestation may wait until the next check before the flow continues.
If a bridge stalls
The burn message remains on-chain and its attestation can be replayed. The bridge does not expire, and Earn retries it approximately every minute until it completes. The funds are not held by Earn or another custodian during this process.
If an inbound bridge is still pending approximately 30 minutes after the burn, the strategy page provides an emergency claim. The strategy owner can claim the minted USDC directly to the owner wallet without Quicknode's involvement.
A claimed deposit does not continue into the destination vault. Deposit the claimed USDC manually if you still want to fund the strategy.