Ethereum’s upcoming Glamsterdam upgrade will change a long-standing rule for basic ETH transfers, meaning the familiar 21,000-gas figure will no longer cover every transaction.
Sending ETH to an address that already exists will continue to cost 21,000 gas. However, transferring ETH to an address that has never been recorded on Ethereum will require additional gas because the network must create and store a new account.
The Ethereum Foundation has urged wallet providers, blockchain explorers and fee-estimation services to review software that assumes every standard ETH transfer costs exactly 21,000 gas. Gas measures the computational resources required to execute transactions on Ethereum, with fees paid in ETH.
Under the new system, transactions involving newly created accounts will incur an additional charge of 183,600 units under a new category called state gas.
Why the 21,000-Gas Rule Is Changing
The 21,000-gas figure has been a standard assumption in Ethereum software for years. Wallets use it to calculate transaction fees, while blockchain infrastructure often relies on it when processing and categorizing basic ETH transfers.
Glamsterdam could cause problems for applications that treat 21,000 gas as both the minimum and maximum required for a simple ETH payment. Such systems could underestimate fees or reject otherwise valid transactions.
The higher cost reflects the additional work required when funds are sent to a new address. A transfer to an existing account only updates balances already maintained by Ethereum. A transfer to a previously unused address requires the network to create a new account entry and maintain that data going forward.
Both transactions have historically carried the same fee despite requiring different amounts of work.
Ethereum Developers Begin Testing the Change
There is still time for developers to adapt their applications before Glamsterdam reaches Ethereum’s mainnet.
The upgrade is scheduled to begin testing on Platåberget, an Ethereum development network where developers can test changes without using real-value assets. It will then move to the Sepolia and Hoodi testnets before being deployed on the main Ethereum network.
Regular ETH users do not need to change anything immediately. The update is primarily a warning for wallet developers, blockchain infrastructure providers, fee calculators and other software that relies on the existing 21,000-gas assumption.
