Testnet
| Blockchain | Domain |
|---|---|
| Arc Testnet | 26 |
| Avalanche Fuji | 1 |
| Base Sepolia | 6 |
| Ethereum Sepolia | 0 |
| HyperEVM Testnet | 19 |
| Sei Atlantic | 16 |
| Solana Devnet | 5 |
| Sonic Testnet | 13 |
| World Chain Sepolia | 14 |
Mainnet
| Blockchain | Domain |
|---|---|
| Arbitrum | 3 |
| Avalanche | 1 |
| Base | 6 |
| Ethereum | 0 |
| HyperEVM | 19 |
| OP | 2 |
| Polygon PoS | 7 |
| Sei | 16 |
| Sonic | 13 |
| Unichain | 10 |
| World Chain | 14 |
Required block confirmations
Before updating the unified USDC balance or issuing attestations, the Gateway API waits for a specific number of block confirmations so that the deposit transaction is unlikely to be reverted. The following table shows the number of block confirmations and the average time to attestation for each supported chain. The average time to attestation is the time it takes for a transaction to be included in a block and confirmed by the network.| Blockchain | Number of blocks | Average time |
|---|---|---|
| Arbitrum | ~65 ETH blocks | ~13 to 19 minutes |
| Arc Testnet | ~1 | ~0.5 seconds |
| Avalanche | 1 | ~8 seconds |
| Base | ~65 ETH blocks | ~13 to 19 minutes |
| Ethereum | ~65 | ~13 to 19 minutes |
| HyperEVM | ~1 | ~5 seconds |
| OP | ~65 ETH blocks | ~13 to 19 minutes |
| Polygon PoS | ~2-3 | ~8 seconds |
| Sei | ~1 | ~5 seconds |
| Solana | ~2-3 | ~8 seconds |
| Sonic | ~1 | ~8 seconds |
| Unichain | ~65 ETH blocks | ~13 to 19 minutes |
| World Chain | ~65 ETH blocks | ~13 to 19 minutes |