In blockchain networks, “gas” refers to the fee required to perform operations like sending tokens or executing smart contracts. These gas fees can be a barrier for users—especially new users who may not own the native currency (like ETH or MATIC) needed to pay these fees.
Gas Stations in blockchain solve this issue by enabling transactions without the sender paying gas fees directly. They are mechanisms that abstract away or sponsor gas costs, allowing for gasless transactions, better UX, and faster adoption of dApps.
1. What Is Gas in Blockchain?
Before diving into gas stations, we must understand gas:
- Gas is a unit that measures the amount of computational effort required to execute operations on a blockchain.
- Every smart contract interaction or token transfer costs gas.
- Gas fees are paid in the blockchain’s native currency:
- Ethereum: Gas paid in ETH
- Polygon: Gas paid in MATIC
- BNB Chain: Gas paid in BNB
For example, sending 1 ETH from one wallet to another might cost 0.001 ETH in gas fees.
2. The Problem with Gas for Users
There are several challenges associated with gas fees:
- Onboarding friction: New users may have tokens like USDT but no ETH to pay gas fees.
- UX complexity: Users must understand gas, set limits, and watch fees fluctuate.
- Scalability issues: During network congestion, gas prices spike, making dApps unusable.
These issues discourage mainstream users from interacting with Web3 applications.
3. What Are Blockchain Gas Stations?
Gas Stations are systems or protocols that allow users to submit transactions without paying gas fees themselves. Instead, a third-party (relayer or sponsor) pays the gas on their behalf.
This mechanism is part of meta-transactions, where a transaction is signed off-chain and submitted by someone else on-chain.
4. How Gas Stations Work (Step by Step)
Step 1: User Prepares Transaction Off-Chain
- The user signs a transaction off-chain using their wallet.
- This transaction contains all the necessary details but doesn’t require gas upfront.
Step 2: Send to Relayer
- The signed transaction is sent to a relayer or gas station network.
- A relayer is a service that takes user-signed transactions and broadcasts them to the blockchain while paying the gas fee.
Step 3: Relayer Submits to Blockchain
- The relayer wraps the transaction into a valid blockchain transaction.
- It submits the transaction on-chain and pays the required gas.
Step 4: dApp or Protocol Reimburses or Rewards Relayer
- The relayer may:
- Get reimbursed by the dApp or project.
- Charge a fee in tokens like USDC or USDT.
- Be incentivized through tokens or staking.
5. The Gas Station Network (GSN)
One of the best-known implementations is the Gas Station Network (GSN), an open-source protocol that enables gasless dApp interactions.
Features:
- Supports meta-transactions.
- Allows dApps to sponsor gas fees.
- Protects users from gas volatility.
- Works across Ethereum and EVM-compatible chains.
GSN Flow:
- User signs a transaction.
- Relayer picks it up.
- Relayer submits it to GSN-compatible smart contract.
- Smart contract verifies signature and executes.
- dApp pays gas via a fund.
6. Biconomy and Other Relayer Services
Biconomy is another major relayer and gas station provider. It allows developers to integrate gasless transactions with minimal code.
Key benefits:
- Simplified Web3 onboarding.
- Supports multiple chains.
- SDKs for easy integration.
- dApps can pay gas in ERC-20 tokens, not just native tokens.
Other platforms include:
- OpenZeppelin Defender Relay
- Gelato Network
- MetaCartel Relayers
7. Use Cases of Gas Stations
1. dApp Onboarding
New users can start using a dApp (like a DeFi app or NFT marketplace) without needing ETH or MATIC in their wallet.
2. Gaming
Blockchain games use gas stations so players don’t get interrupted by wallet pop-ups and gas fees during gameplay.
3. DeFi & NFT Platforms
dApps like decentralized exchanges and NFT minting platforms integrate gasless options for smoother transactions.
4. DAO Voting
Members can vote on proposals without paying gas, encouraging participation in governance.
8. Who Pays the Gas?
Depending on the setup, gas fees can be paid by:
- dApp Developers: Using sponsored wallets or relayer accounts.
- Users: Indirectly, in ERC-20 tokens (e.g., DAI, USDC).
- Protocols: From community or DAO treasuries.
- Advertisers or Partners: In exchange for attention or engagement.
9. Benefits of Gas Stations
- Improved UX: No need for native tokens to interact.
- Better Adoption: Users can onboard instantly.
- Gas Abstraction: Developers can offer seamless backend operations.
- Scalability: Enables batching of transactions and fee optimizations.
10. Limitations and Risks
- Centralization Risk: Relayers could be centralized or censor transactions.
- Spam Attacks: Malicious users could abuse gas sponsorship.
- Signature Complexity: Requires off-chain signing and sometimes custom wallet logic.
- Security: Poorly implemented meta-transactions may be vulnerable to replay attacks.
11. The Future of Gasless Transactions
- Wallet-level Integration: MetaMask and WalletConnect may integrate GSN-like features natively.
- Account Abstraction (ERC-4337): Future Ethereum upgrades aim to natively support gas abstraction without relayers.
- Multi-chain Support: More protocols will use relayers across Ethereum, Arbitrum, Polygon, Optimism, etc.
- Sponsored UX: Projects will offer free or subsidized usage as part of their business model.
12. Real World Example
Imagine a user named Rahul:
- He wants to mint an NFT on a platform built on Polygon.
- Rahul only has USDT in his wallet—not MATIC.
- The NFT minting dApp supports Biconomy gasless transactions.
- Rahul signs a mint request.
- Biconomy’s relayer pays the MATIC gas.
- The transaction completes; Rahul pays nothing in MATIC.
- This smooth experience keeps Rahul engaged and likely to return.