The Ethereum Foundation has issued a warning to Layer 1 contract maintainers ahead of the Glamsterdam upgrade, expected in Q4 2026, that two gas repricing proposals could cause a small number of smart contracts to break or degrade without developer updates.
The upgrade includes EIP-8037 and EIP-8038. EIP-8037 increases and standardizes costs for creating accounts, storage slots, and deployed bytecode. EIP-8038 raises costs for accessing existing state, including SLOAD, SSTORE, cold account access, EXTCODESIZE, and EXTCODECOPY.
The Foundation said the changes reflect the measured workload of operations on Ethereum's larger state. Gas prices for these operations were last adjusted during the 2021 Berlin upgrade, and recent gas limit increases have accelerated state growth. The new schedule is derived from a performance target supporting roughly three times higher base throughput.
After replaying historical mainnet transactions under the proposed schedule, the Foundation found that most transactions produced the same outcome. However, a smaller group showed different results: some used different gas amounts, some failed because original gas limits became insufficient, and an even smaller group could remain broken despite substantially higher limits. Those contracts often depend on fixed gas assumptions, such as Solidity's 2,300-gas transfer and send stipends, hardcoded call values, gasleft() checks, and fixed gas limits.
Teams behind the most affected contracts are already receiving direct outreach. Developers can search an affected-contracts database by address to identify failure types and responsible repricing, and can test fixes on the Platåberget testnet, also known as glam-devnet-8. Wallet and RPC providers must update gas estimation for the new schedule to avoid underestimating transaction costs. The repricing is already live on devnets and will move to public testnets before mainnet activation.
Glamsterdam is named from the combination of Amsterdam as the execution layer upgrade and Gloas as the consensus layer upgrade, with a focus on scaling Ethereum's Layer 1 by reorganizing how the network handles transactions and manages its growing database.
