Glamsterdam gas repricing: which contracts are affected and which are not

In short

On 24 August 2026 the Ethereum Foundation's protocol research, EthPandaOps and specifications teams published a joint post: the planned Glamsterdam upgrade changes the gas cost of some operations, and developers are asked to check their own contracts now.

The main message is not a warning. It is a call to test.

Most contracts are unaffected

The post groups transactions by how they are affected, and says this of the group with no change:

"The large majority of transactions fall here"

So the default state is "unaffected". The group that can break is narrow and defined:

"Contracts in the last group typically rely on hardcoded gas assumptions, such as fixed stipends...hardcoded gas values in calls, logic that branches on gasleft()."

Three patterns stand out: fixed stipends, hardcoded gas values inside calls, and logic that branches on the result of gasleft(). For a contract carrying none of these, the announcement asks for nothing.

Two tools the developer has

The post gives two concrete places to go. The first is a lookup:

"you can check whether a contract may be affected by pasting the contract address into the affected-contracts search."

The second is a testnet: Platåberget (glam-devnet-8) runs the new schedule and is described as available now.

The suggested fix is in most cases simple, raising the gas limit:

"If your contract is fixable with a gas-limit increase, update the gas limits your frontend, infra, or users supply."

This does not mean the upgrade is live

The post is a preparation call. It gives no date for mainnet activation, and no such date is verified here. A testnet running the schedule does not mean the change is in force on mainnet.