In the evolving landscape of blockchain development, Smart Wallets are redefining how users interact with decentralized applications. Built on ERC-4337, a standard for account abstraction, Smart Wallets eliminate many of the friction points associated with traditional externally owned accounts (EOAs). This guide dives into what Smart Wallets are, how to create and manage them, and how they enable advanced features like batch transactions and gas sponsorship—all while maintaining security and cross-chain compatibility.
Whether you're building on Base or preparing for multi-network deployment, understanding Smart Wallets is essential for modern dApp development.
What Is a Smart Wallet?
A Smart Wallet is an ERC-4337-compatible wallet that leverages account abstraction to provide enhanced functionality beyond standard crypto wallets. Unlike traditional wallets controlled directly by private keys, Smart Wallets operate through smart contracts, enabling programmable interactions such as transaction batching, gasless operations, and social recovery mechanisms.
The Smart Wallet API uses the same underlying smart contract as the Frontend SDK, ensuring consistency across development environments. Currently in beta, this technology offers developers a powerful backend wallet solution with built-in support for advanced features.
One of the standout benefits? A Smart Wallet provides a single address that works across all EVM-compatible networks. While only Base Mainnet and Base Sepolia are supported today, future network expansions will automatically extend support to existing wallets—without changing their address.
👉 Discover how easy it is to integrate next-gen wallet features into your dApp.
Core Components of a Smart Wallet
Each Smart Wallet has a single owner, which is an account backed by a private key responsible for signing transactions. Think of this private key as the master password to your wallet—its security is paramount.
For added context:
A private key grants full control over a wallet’s assets. If lost or compromised, recovery may not be possible. Always follow best practices for key management.
Key Features Enabled by Account Abstraction
- Paymaster Integration: Sponsor gas fees so users can transact without holding native tokens.
- Batch Transactions: Execute multiple operations in a single UserOperation.
- Cross-Network Compatibility: Use the same wallet address across EVM chains.
- Backend Wallet Management: Ideal for custodial or semi-custodial dApp architectures.
Creating a Smart Wallet
To get started, we recommend using Viem—a lightweight Ethereum client for TypeScript—to generate the owner account and private key.
Below is a complete example of how to create a Smart Wallet using the Coinbase SDK:
import { generatePrivateKey, privateKeyToAccount } from "viem/accounts";
import { createSmartWallet } from "@coinbase/coinbase-sdk";
// Generate a secure private key (must be stored safely!)
const privateKey = generatePrivateKey();
const owner = privateKeyToAccount(privateKey);
// Create the Smart Wallet instance
const smartWallet = await createSmartWallet({
signer: owner
});
// Retrieve the wallet address
const smartWalletAddress = smartWallet.address;
console.log("Smart Wallet Address:", smartWalletAddress);📌 Important: The private key must be securely stored and persisted across sessions. Consider encrypting it before saving to a database or secure vault.
Refer to the SmartWallet SDK docs for a full list of available methods and configurations.
Sending a UserOperation
In ERC-4337, transactions are executed via UserOperations, which are bundled off-chain and processed by a network of bundlers. This mechanism enables powerful capabilities like gas sponsorship and multi-call execution.
Use sendUserOperation to initiate actions from your Smart Wallet. It supports both individual and batched calls, and integrates seamlessly with paymasters.
Here’s an example of a batch transaction that sends ETH and invokes a smart contract function:
const ABI = [
{
inputs: [
{ internalType: "uint256", name: "a", type: "uint256" },
{ internalType: "bool", name: "b", type: "bool" },
{ internalType: "address", name: "c", type: "address" }
],
name: "someFunction",
outputs: [],
stateMutability: "nonpayable",
type: "function"
}
] as const; // 'as const' is required for proper TypeScript inference
const userOperation = await smartWallet.sendUserOperation({
calls: [
{
to: "0x1234567890123456789012345678901234567890",
value: parseEther("0.0000005"),
data: "0x"
},
{
to: "0xb720E683CB90838F23F66a37Adb26c24e04D1b60",
abi: ABI,
functionName: "someFunction",
args: [123n, true, "0x3234567890123456789012345678901234567890"]
}
],
chainId: 84532 // Base Sepolia
});
// Wait for the operation to complete
const userOperationResult = await waitForUserOperation(userOperation);
if (userOperationResult.success) {
console.log("Transaction hash:", userOperationResult.transactionHash);
}💡 Tip: Always include as const when defining ABIs in TypeScript to ensure correct type resolution.
Understanding Paymaster Support
Gas sponsorship is one of the most user-friendly features of Smart Wallets. On Base Sepolia, the CDP API automatically covers gas costs—meaning you can send UserOperations without any ETH in the wallet.
On Base Mainnet, you can pass a Paymaster URL to sendUserOperation to sponsor gas fees:
const userOperation = await smartWallet.sendUserOperation({
calls: [...],
chainId: 8453,
paymasterUrl: "https://paymaster.example.com/api"
});This allows developers to offer gasless experiences, lowering barriers to entry for new users.
For more details, check out the Paymaster documentation.
👉 Start building gasless experiences with cutting-edge wallet infrastructure.
Securing and Managing Your Smart Wallet
Security remains critical—even with advanced wallet architectures.
Storing the Private Key Safely
The owner’s private key must be protected at all costs. As the developer, you are responsible for secure storage. Recommended practices include:
- Encrypting the key before storing in databases
- Using hardware security modules (HSMs) in production
- Avoiding logging or exposing keys in code
Never hardcode private keys in source files.
Re-instantiating a Wallet
When starting a new session, you’ll need both the private key and the original smart wallet address to restore access.
Here’s how to re-instantiate:
const restoredOwner = privateKeyToAccount(privateKey);
const smartWallet = await createSmartWallet({
signer: restoredOwner,
// Optionally provide the known address if pre-deployed
});Once restored, you can resume all operations—sending transactions, querying balances, or integrating with dApps.
Frequently Asked Questions (FAQ)
Q: Can I use a Smart Wallet on networks other than Base?
A: Currently, only Base Mainnet and Base Sepolia are supported. However, the design ensures that when new EVM networks are added, your wallet address will remain consistent across chains.
Q: Do I need ETH to pay for gas?
A: Not always. On Base Sepolia, gas is sponsored via the CDP API. On Base Mainnet, you can use a paymaster service to sponsor fees—enabling truly gasless transactions.
Q: What happens if I lose my private key?
A: Since the owner account relies on a private key, losing it means losing access to the Smart Wallet. There is no built-in recovery mechanism unless implemented separately by the developer.
Q: Are batch transactions atomic?
A: Yes—all calls within a single UserOperation execute atomically. If one fails, the entire operation reverts.
Q: How does this differ from a regular MetaMask wallet?
A: Traditional wallets like MetaMask are EOAs controlled directly by private keys. Smart Wallets are contract-based, enabling programmable features like paymasters, batched calls, and future upgrades—without changing the user’s address.
Q: Is this suitable for production apps?
A: While currently in beta, Smart Wallets are being actively tested and refined. For production use, ensure robust key management and monitor updates from the SDK maintainers.
👉 Explore seamless integration of scalable, user-friendly wallet solutions today.
Final Thoughts
Smart Wallets represent a significant leap forward in blockchain usability and developer flexibility. By abstracting away complex user interactions and enabling features like sponsored transactions and cross-chain continuity, they pave the way for mass adoption.
With tools like Viem and the Coinbase SDK, getting started is straightforward—but securing keys and understanding account abstraction deeply will separate successful implementations from risky ones.
As more networks adopt ERC-4337 standards, early adopters will have a clear advantage in delivering smooth, intuitive experiences to their users.
Core Keywords: Smart Wallet, ERC-4337, account abstraction, paymaster, gas sponsorship, batch transactions, Base Mainnet, UserOperation