---
title: Gasless transactions with EIP-7702, explained
description: What gasless (sponsored) transactions are, how a managed EIP-7702 relay makes them work without an ERC-4337 bundler, and how Kryard implements them — the user signs a 7702 authorization and a batch digest, and the relay fronts gas and broadcasts a type-4 transaction.
---

# Gasless transactions, explained

**TL;DR — A gasless (sponsored) transaction lets a user act on-chain without holding
the native gas token.** Someone else — a *relayer* or *paymaster* — pays the gas. In
Kryard, the user signs a lightweight **EIP-7702 authorization** plus a **batch
digest**; Kryard's managed relay signs the outer transaction, fronts the gas, and
broadcasts a **type-4** transaction. No ERC-4337 bundler, no smart-contract wallet to
deploy — the user's own EOA executes the batch.

## Why "gasless" matters

New users don't have ETH (or the chain's native token) to pay gas, which kills
onboarding. Gasless UX removes that wall: the app sponsors gas, or lets the user pay
it in a token they already hold (see [Pay gas in any token](/relay/erc20-gas)).

## How Kryard does it (managed EIP-7702 relay)

1. **The user signs two things** — an [EIP-7702](https://eips.ethereum.org/EIPS/eip-7702)
   authorization that lets their EOA temporarily execute a delegate's code, and an
   EIP-712 digest over the batch of calls they want to make. Both are cheap
   off-chain signatures; the user never needs gas.
2. **Kryard's relay assembles and pays.** It builds a **type-4 (SetCode)**
   transaction carrying the user's authorization, signs the outer transaction with a
   custodied relayer key, and **fronts the gas**.
3. **The chain executes the batch as the user's EOA.** Under the 7702 authorization,
   the EOA runs the delegate's `execute(...)` for the user-signed batch — one atomic,
   sponsored transaction.

The user gets **smart-wallet UX** (sponsored, batched execution) from a **plain EOA**,
with **no bundler and no deployed contract wallet**.

## What the user never does

- Hold or spend the native gas token (unless you want them to pay in an ERC-20).
- Deploy a smart-contract wallet.
- Run or trust an ERC-4337 bundler.

## Kryard's guarantees

- The relay only signs and broadcasts what the user **authorized** with their 7702
  signature — it can't substitute other calls.
- Signing keys are KMS-encrypted; the API never decrypts them and they never leave an
  isolated signer.
- If a user pays gas in a token, the on-chain `KryardDelegate` reimburses the relayer
  an **exact, user-signed** fee that can't be inflated.

## Next

- [Quickstart](/relay/quickstart) — sponsor your first gasless batch.
- [Pay gas in any token](/relay/erc20-gas) — settle gas in USDC or any ERC-20.
- [EIP-7702 vs ERC-4337](/concepts/7702-vs-4337) — why Kryard needs no bundler.