Unsupported chain or network

HTTP status: 400 Retryable: No

Description

The chain and network combination you requested is not supported by this endpoint. Not every chain is available on every network (mainnet, testnet, etc.).

Resolution

Check the endpoint documentation for the list of supported chains and networks. Use GET /chains/v2 to enumerate available combinations and confirm the network you need is listed.

Example response

{
  "error": {
    "code": "unsupported_chain",
    "docUrl": "https://docs.blockdaemon.com/errors/unsupported_chain",
    "message": "The chain/network combination 'eip155/999999' is not supported",
    "occurredAt": "2026-02-10T10:00:00Z",
    "requestId": "req_abc123xyz",
    "status": 400
  }
}