eth_sendRawTransaction

eth_sendRawTransaction broadcasts a fully signed, RLP-encoded transaction to Base — Coinbase's OP Stack optimistic rollup that uses ETH for gas — and returns the resulting transaction hash. You sign the transaction client-side (with viem, ethers, or web3.js) and submit the serialized hex; the private key never leaves your machine. The node forwards it toward the Base sequencer, which orders it into a block roughly every 2 seconds. Be sure the transaction is signed for chain ID 8453 (0x2105) to prevent replay, and send it to https://base.therpc.io/YOUR_API_KEY.

Use cases

• Submit an ETH transfer on Base after signing it offline, then track inclusion by the returned hash.
• Deploy a smart contract by omitting the to field and setting data to the contract creation bytecode; the deployed address comes back later in the receipt's contractAddress.
• Execute a contract write such as an ERC-20 transfer or an Aerodrome swap by signing a transaction whose data holds the encoded function call.

Parameters

Response

Example request

1curl https://base.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5    "jsonrpc": "2.0",
6    "method": "eth_sendRawTransaction",
7    "params": ["0x..."],
8    "id": 1
9  }'

Try it live in the Base playground.

Errors & troubleshooting

Common pitfalls

• The returned hash only proves the node accepted the transaction into its mempool — not that it is confirmed. Poll eth_getTransactionReceipt until you get a non-null receipt to confirm inclusion on Base.
• A successful broadcast does not guarantee on-chain success: a receipt with status: "0x0" means the transaction was included in a Base block but reverted, and the ETH gas was still spent.
• Always fetch a fresh nonce with eth_getTransactionCount immediately before signing — on Base's fast ~2s blocks, a stale nonce easily collides with a transaction you just sent and triggers a "nonce too low" error.

Supported networks

• Mainnet — Chain ID: 8453
• Sepolia — Chain ID: 84532

See also

• eth_getTransactionReceipt
• eth_estimateGas
• eth_call

1curl https://base.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H 'Content-Type: application/json' \
4  -d '{"jsonrpc":"2.0","id":1,"method":"eth_sendRawTransaction","params":[""]}'