Which chains support x402?
As of April 2026 the chains with production x402 facilitator support via Coinbase's reference facilitator are Base, Solana, Polygon, Arbitrum, and World Chain. Additional chains including Avalanche, Sei, XDC, and SKALE have community or ecosystem facilitator implementations at varying maturity (production or beta). Base and Solana were the launch chains, chosen for their low gas fees and native USDC liquidity. The x402 spec is chain-agnostic and uses CAIP identifiers, so any chain with a facilitator implementation can be added. Ethereum mainnet works but is typically too expensive for true micropayments. Expect the list to keep growing.