> For the complete documentation index, see [llms.txt](/llms.txt). # Bundler methods (ERC-4337) Infura supports [ERC-4337](https://docs.erc4337.io/) bundler JSON-RPC methods that enable you to build account abstraction (AA) experiences like gas sponsorship (paymasters), ERC-20 gas payment, session keys, or batched actions using smart accounts. If your dapp or wallet uses smart accounts, use the bundler JSON-RPC methods. If you use externally owned accounts (EOAs) only, use standard Ethereum JSON-RPC methods. info AA moves validation and fee-payment logic into smart contracts. Instead of sending raw transactions from an EOA, clients submit [user operations (UserOps)](#user-operations) to a bundler. The bundler collects and simulates these operations, then executes them through a [shared coordination contract (EntryPoint)](#entrypoint-contract) on the network. Smart accounts are smart contract-based wallets that serve as the foundation of AA. They embed custom logic for authentication, authorization, network fee payment, nonce management and execution. info Refer to the [official Pimlico documentation](https://docs.pimlico.io/references/bundler)for more about the bundler methods and [EntryPoint errors](https://docs.pimlico.io/references/bundler/entrypoint-errors#entrypoint-errors). ## User operations[​](#user-operations "Direct link to User operations") A user operation (UserOp) is an is an offchain request that a bundler later includes onchain by calling the EntryPoint. UserOps go to a dedicated mempool watched by bundlers instead of being broadcast as raw L1/L2 transactions. ## EntryPoint contract[​](#entrypoint-contract "Direct link to EntryPoint contract") The EntryPoint contract is the shared coordination contract defined by ERC-4337. Bundlers call them to validate and execute user operations (UserOps) from smart accounts. At a high level, an EntryPoint: - Runs the ERC-4337 validation and execution. - Enforces nonce and signature checks exposed by each smart account. - Coordinates fee payment (including paymasters). - Executes the requested calls onchain. The bundler supports calling multiple EntryPoint versions (v0.6 and v0.7/v0.8) through the same set of RPC methods, allowing it to handle both older and modern smart account schemes. Use the [eth_supportedEntryPoints](/services/reference/ethereum/json-rpc-methods/bundler/eth%5Fsupportedentrypoints/)method to fetch the EntryPoint addresses supported by the bundler. ## Supported methods[​](#supported-methods "Direct link to Supported methods") The following bundler methods are available on the [supported networks](#supported-networks): - [eth_sendUserOperation](/services/reference/ethereum/json-rpc-methods/bundler/eth%5Fsenduseroperation/): Submits a user operation to be included onchain. - [eth_estimateUserOperationGas](/services/reference/ethereum/json-rpc-methods/bundler/eth%5Festimateuseroperationgas/): Simulates the user operation and estimates the appropriate gas limits. - [eth_getUserOperationReceipt](/services/reference/ethereum/json-rpc-methods/bundler/eth%5Fgetuseroperationreceipt/): Fetches the receipt of a user operation. - [eth_getUserOperationByHash](/services/reference/ethereum/json-rpc-methods/bundler/eth%5Fgetuseroperationbyhash/): Fetches the user operation by hash. - [eth_supportedEntryPoints](/services/reference/ethereum/json-rpc-methods/bundler/eth%5Fsupportedentrypoints/): Fetches the EntryPoint addresses supported by the bundler. - [pimlico_getUserOperationGasPrice](/services/reference/ethereum/json-rpc-methods/bundler/pimlico%5Fgetuseroperationgasprice/): Returns the gas prices that must be used for the user operation. - [pimlico_getUserOperationStatus](/services/reference/ethereum/json-rpc-methods/bundler/pimlico%5Fgetuseroperationstatus/): Returns the user operation status. - [pimlico_simulateAssetChanges](/services/reference/ethereum/json-rpc-methods/bundler/pimlico%5Fsimulateassetchanges/): Simulates a user operation to predict the asset changes it will cause. ## Supported networks[​](#supported-networks "Direct link to Supported networks") Bundler methods are active on the following networks: - [Arbitrum](/services/reference/arbitrum/json-rpc-methods/bundler/) (mainnet and Sepolia) - [Avalanche](/services/reference/avalanche-c-chain/json-rpc-methods/bundler/) (mainnet and Fuji) - [Base](/services/reference/base/json-rpc-methods/bundler/) (mainnet and Sepolia) - [Blast](/services/reference/blast/json-rpc-methods/bundler/) (mainnet and Sepolia) - [BNB Smart Chain](/services/reference/bnb-smart-chain/json-rpc-methods/bundler/) (mainnet and testnet) - [Celo](/services/reference/celo/json-rpc-methods/bundler/) (mainnet and Alfajores) - [Ethereum](/services/reference/ethereum/json-rpc-methods/bundler/) (mainnet and Sepolia) - [Linea](/services/reference/linea/json-rpc-methods/bundler/) (mainnet and Sepolia) - [Mantle](/services/reference/mantle/json-rpc-methods/bundler/) (mainnet and Sepolia) - [opBNB](/services/reference/opbnb/json-rpc-methods/bundler/) (mainnet) - [Optimism](/services/reference/optimism/json-rpc-methods/bundler/) (mainnet and Sepolia) - [Polygon](/services/reference/polygon-pos/json-rpc-methods/bundler/) (mainnet and Amoy) - [Scroll](/services/reference/scroll/json-rpc-methods/bundler/) (mainnet and Sepolia) - [Sei](/services/reference/sei/json-rpc-methods/bundler/) (mainnet and testnet) - [Unichain](/services/reference/unichain/json-rpc-methods/bundler/) (mainnet and Sepolia) info [Contact support](https://support.infura.io/) if you require bundler method activation on a network not listed here that's currently supported by Pimlico.