What Is ERC-4337? Account Abstraction and Gas in Any Token

The problem: EOAs and the pain of native gas

Every ordinary Ethereum wallet is an externally owned account (EOA): an address controlled by a single private key. EOAs are simple, but they are also rigid. They can only be triggered by that one key, they can only execute one call at a time, and — critically — they can only pay transaction fees in the chain's native token. To move a stablecoin on Ethereum you still need ETH for gas. To do the same on a rollup you need that rollup's native asset. The result is a familiar new-user trap: your funds are in one token, but the network refuses to act until you also hold a different one.

Beyond gas, EOAs offer no built-in recovery. Lose the key and the account is gone forever. There is no way to batch an approve-and-swap into a single atomic step, no way to delegate a narrow permission to a game or dapp, and no way for a third party to sponsor your fees. For years these limits were treated as facts of life, because changing them seemed to require changing Ethereum itself.

What ERC-4337 actually is

ERC-4337 is the standard that delivers account abstraction without touching the consensus layer. Instead of a hard fork that redefines how accounts work at the protocol level, it introduces a higher-level system that lives entirely in smart contracts and off-chain infrastructure. Accounts become programmable smart contracts, and the logic that validates a transaction — who may sign it, in what token fees are paid, what limits apply — is written in code you control rather than hardwired into the base protocol.

The mechanism is a second, parallel alt-mempool. Regular transactions flow through Ethereum's normal mempool; ERC-4337 intents flow through their own. Because none of this required a protocol change, ERC-4337 shipped as an application-layer standard and has been live on Ethereum mainnet since 2023, then across most major EVM rollups. That is its defining trick: real account abstraction, retrofitted onto an unchanged blockchain.

The core pieces

Four moving parts make it work. A UserOperation is the ERC-4337 equivalent of a transaction — a structured object describing what the account wants to do, which you sign and drop into the alt-mempool. A Bundler is an off-chain actor that collects these UserOperations, packages several together, and submits them on-chain as a single ordinary transaction, paying the actual ETH gas up front. The EntryPoint is one canonical, audited smart contract that every bundle passes through; it verifies each operation and invokes the target smart account, acting as the trusted choreographer for the whole flow.

The fourth piece is the Paymaster: an optional contract that agrees to cover gas for a UserOperation, either sponsoring it outright or accepting payment in an ERC-20 token instead of ETH. The paymaster is where most of the user-facing magic originates, and it deserves its own treatment — see what a paymaster is for the full picture.

What it unlocks

Once fee logic and validation are programmable, a lot becomes possible. Paying gas in any token is the headline: a paymaster can let you settle fees in a stablecoin or a project token while it handles the ETH behind the scenes — the core idea behind gas abstraction. Sponsored or gasless transactions let an app pay fees for its users, smoothing onboarding. Batching collapses multi-step flows — approve then swap — into one atomic UserOperation. Session keys grant a dapp a scoped, time-limited permission so you are not signing every single action. And social recovery replaces the single fragile private key with policies like multi-signer approval or trusted guardians, so a lost device no longer means lost funds.

Scope: ERC-4337 is EVM-only

It is worth being precise about reach. ERC-4337 is an Ethereum standard built around the EVM, the EntryPoint contract, and the alt-mempool. It runs on Ethereum and EVM-compatible chains — not on non-EVM networks. Solana and TON never had EOAs in the same sense and do not use ERC-4337 at all; instead they achieve comparable outcomes through their own designs. On Solana a fee-payer can be named separately from the transaction's signer, so a relayer can cover fees. TON uses a smart-contract-wallet model with relayers that can pay on a user's behalf. The user-facing effect — someone else's infrastructure fronts the native fee — rhymes with a paymaster, but the plumbing is entirely different. ERC-4337 itself does not execute on Solana or TON.

Status and limits as of 2026

As of 2026 ERC-4337 is mature and widely deployed, with a shared EntryPoint and a growing bundler and paymaster ecosystem. The main frictions are structural: smart accounts cost more gas to deploy and operate than bare EOAs, the bundler layer adds infrastructure to run or rely on, and support is uneven across tooling. A complementary track, EIP-7702, adds protocol-level support letting existing EOAs temporarily adopt smart-account behavior, narrowing the gap between the two models. Expect the two approaches to coexist and converge rather than one simply replacing the other.

How WATS uses this

In the WATS Hot Wallet, every action — transfers, swaps, staking — is charged in a single token, ATS, instead of the chain's native gas. On EVM chains that is done with an ERC-4337 paymaster: WATS does not turn your wallet into a custodial account, and it never holds a key — WATS is non-custodial, and you hold your own. Because ATS is a LayerZero OFT, one balance settles fees across EVM, Solana and TON, and the ATS collected as fees is burned, reducing supply from 100,000,000 toward a 30,000,000 floor. That precise combination — ERC-4337 plus OFT single-token fees charged instead of native gas, paired with that burn — is what makes WATS the first and only wallet of its kind; the mechanics are laid out on the ATS fee page.