Gasless Transactions & MetaMask: Relay Mechanisms & Sponsored Gas Models

Introduction

For many newcomers, one of the most confusing parts of using Ethereum and other blockchains is gas fees. Every transaction—whether swapping tokens, minting an NFT, or interacting with a DeFi protocol—requires gas, and that fee must be paid in the network’s native token (e.g., ETH on Ethereum, MATIC on Polygon). This creates friction for users and often serves as a barrier to adoption.

Enter gasless transactions, a concept where users interact with decentralized applications (dApps) without directly paying for gas. Instead, transactions are relayed or sponsored by other parties through innovative models. MetaMask, the most widely used non-custodial wallet, is playing an active role in supporting these new approaches, making blockchain interactions more seamless for both beginners and power users.

This article takes a deep dive into how gasless transactions work, the role of MetaMask in enabling them, the mechanics of relay mechanisms and sponsored gas models, and why they might represent the next step toward mainstream adoption of Web3.

What Are Gasless Transactions?

A gasless transaction allows users to sign and submit blockchain interactions without holding the native gas token. Instead, a third party—often called a relayer or sponsor—pays the transaction fee on their behalf.

This doesn’t mean the blockchain suddenly becomes “free.” Someone always pays the gas; the difference lies in who covers the cost and how it’s structured.

For example:

• In a sponsored model, a dApp or protocol pays the gas fee to onboard users smoothly.

• In a relay mechanism, a third-party infrastructure provider facilitates the transaction and recoups costs in various ways (fees, tokenized models, or incentive structures).

For users, this means frictionless onboarding—no more needing ETH in your wallet just to send a token or try out a dApp.

How MetaMask Enables Gasless Transactions

MetaMask has gradually integrated support for gas abstraction mechanisms that make it easier for developers to implement gasless experiences in their dApps. The core enabler here is MetaMask Snaps and the MetaMask SDK, which allow developers to build custom transaction flows, including relayers.

Key MetaMask features that support gasless models:

1. Transaction Signing Flexibility – MetaMask separates signing from broadcasting. This allows relayers to take a signed transaction and submit it on behalf of the user.

2. EIP-712 & Meta-Transactions – MetaMask supports EIP-712 typed data signing, the backbone of meta-transactions. Users sign a structured message, and a relayer executes it on-chain while paying the gas.

3. Integration with Paymasters – On Layer-2s and rollups, Account Abstraction (EIP-4337) introduces “paymasters” that can fund gas fees in creative ways, and MetaMask is already aligning with these standards.

By giving developers the tools to implement these flows, MetaMask helps abstract away gas complexity without compromising user control or wallet security.

Relay Mechanisms: How They Work

A relay mechanism is essentially middleware between the user and the blockchain.

Step-by-step breakdown:

1. The user signs a transaction in MetaMask without gas.

2. Instead of broadcasting directly, the transaction is sent to a relayer service.

3. The relayer wraps the transaction in its own and pays the required gas in ETH (or the native token).

4. The transaction is confirmed on-chain, and the user sees it executed without ever handling gas.

Common relayer setups include:

• Centralized Relayers: Provided by dApps themselves (common for onboarding).

• Decentralized Relayer Networks: Services like OpenZeppelin Defender or Biconomy run distributed relayers for resilience and neutrality.

The relay mechanism ensures UX simplicity, especially for users who don’t even know what gas is.

Sponsored Gas Models

A sponsored gas model flips the economics: instead of the user or relayer bearing the cost, the dApp or project pays for gas.

This is often used for:

• Onboarding campaigns – Free first transactions for new users.

• NFT mints – Projects covering gas to reduce friction.

• DeFi adoption – Protocols subsidizing usage to attract liquidity.

Some advanced sponsored models use:

• Stablecoins to cover gas – Paymasters allow gas fees to be settled in USDC or other tokens.

• Tokenomics incentives – Native tokens that reward relayers or cover gas through staking mechanisms.

MetaMask’s integration with these models ensures users can transact even if they have zero ETH or MATIC in their wallets.

Benefits of Gasless Transactions with MetaMask

1. Seamless Onboarding – Users can interact with dApps instantly without buying ETH first.

2. Mainstream Accessibility – Reduces cognitive load for non-crypto natives.

3. Boosted Adoption – dApps attract more users by removing upfront costs.

4. Improved UX – Less friction leads to better retention.

5. Flexibility for Developers – MetaMask SDK enables custom setups for relayers and paymasters.

Challenges & Risks

While gasless transactions are powerful, they come with caveats:

• Centralization of Relayers – If a single relayer goes down or censors, the system breaks.

• Sustainability of Sponsorship – Paying gas for users isn’t always economically viable long-term.

• Security Risks – Poorly implemented relayers can manipulate or front-run transactions.

• Regulatory Concerns – Sponsored models could be interpreted as custodial if not carefully designed.

MetaMask mitigates these risks by keeping user signing keys self-custodied while letting developers experiment with different fee abstraction methods.

The Future: Gas Abstraction and MetaMask’s Role

The evolution of gasless transactions is tied closely to Account Abstraction (EIP-4337), which aims to standardize gas payment flexibility at the protocol level. In this model:

• Users can choose how they pay gas (stablecoins, ERC-20 tokens, or even sponsored).

• Smart contract wallets replace EOAs (Externally Owned Accounts).

• Paymasters and bundlers become core parts of the ecosystem.

MetaMask is expected to play a critical role here by:

• Supporting EIP-4337 wallets and flows.

• Integrating decentralized relayer networks.

• Providing developer SDKs to implement customized gasless experiences.

In other words, gasless transactions will no longer be a “hack” but a native feature of Ethereum and beyond—with MetaMask at the center.

Conclusion

Gasless transactions represent one of the biggest UX breakthroughs in blockchain. By abstracting away the complexity of gas fees, MetaMask and its integration with relayers, paymasters, and sponsored models pave the way for mass adoption of Web3.

For users, this means no more worrying about ETH in your wallet just to try a dApp. For developers, it’s a chance to onboard millions of new users with smooth, Web2-like experiences.

As Ethereum moves toward account abstraction and MetaMask deepens its role as the gateway to decentralized apps, gasless transactions will become less of an experiment and more of a standard.

The future of Web3 isn’t just decentralized—it’s frictionless. And MetaMask is proving to be the key to unlocking it.