Why does my wallet say insufficient funds for gas?

An insufficient funds for gas error means your wallet does not have enough of the network's own coin to pay the transaction fee. It can appear even when the wallet holds plenty of other tokens, because those tokens usually cannot pay the fee. The confirm button often turns grey for the same reason.

Why does MetaMask say insufficient gas?

MetaMask's help center says the error appears when an account lacks enough of the network's native token to cover gas. Every transaction needs gas, including token transfers and app interactions, and the cost changes with demand. Our guide to gas fees explains how that cost is set.

The native token depends on the network. MetaMask lists these examples:

• Ethereum and layer 2 networks such as Arbitrum and Optimism use ETH.
• BNB Chain uses BNB.
• Polygon uses POL, formerly MATIC.
• Avalanche uses AVAX.

So a wallet with ETH on Ethereum but nothing on Polygon will see the error when it tries to move tokens on Polygon. The balances on each network are separate.

The check also covers the amount being sent. Node provider Blockdaemon describes the error as a balance too small to cover the transfer value plus the estimated gas cost. Trying to send an entire ETH balance can trigger it, because nothing is left for the fee.

Why do you need ETH to send tokens?

Ethereum.org states that gas fees must be paid in ether. A token such as USDC or an ERC-20 token is a balance stored inside a smart contract. Moving it means asking the network to run that contract, and the network charges for the work in its own currency.

This catches people out with wrapped ether too. WETH is worth the same as ETH but is a token, so it cannot pay gas directly.

How do you get gas for a transaction?

MetaMask lists several routes:

• Send some of the native coin to the account from another wallet or an exchange.
• Buy it through an on-ramp, a service that sells crypto for regular money, or inside the wallet on supported networks.
• Swap another token for it on a decentralized exchange, if the account can already pay for that swap.

Some wallets also offer a way around the problem. As of October 2026, MetaMask's Gas Station lets users pay the network fee in supported tokens, such as USDC or USDT, on networks including Ethereum, BNB Smart Chain, Arbitrum, Polygon, Linea and Base. MetaMask says the fee shown includes a small MetaMask charge, and the feature requires certain settings to be switched on.

Does a failed transaction still cost gas?

It depends where it fails. Ethereum.org says a transaction rejected before it is included in a block uses no gas. One that runs out of gas while executing is reversed, yet the gas is still spent. An insufficient funds warning in the wallet normally stops the transaction before it is sent, so no fee is paid at that point.