Ethereum developers are warning that the upcoming Glamsterdam upgrade could cause problems for wallets, gas estimators, indexers, and other applications that rely on fixed gas assumptions.
The Ethereum Foundation’s Protocol DevOps team said that software using hardcoded gas limits may stop working correctly once the upgrade is activated. Developers have been urged to test their applications on the Platåberget testnet, where Glamsterdam is scheduled to go live on Aug. 20 before later expanding to Sepolia and Hoodi test networks.
One of the biggest changes comes from EIP-8037, which introduces a new way of charging for blockchain state creation. Currently, many applications assume that a simple ETH transfer always costs 21,000 gas. After Glamsterdam, that assumption will no longer be true in every situation.
Sending ETH to an existing account will still cost 21,000 gas. However, sending ETH to a brand-new account will require additional gas because creating a new account adds permanent data to Ethereum’s state. The new system introduces a separate “state gas” charge for these actions.
Because of this change, wallets and gas estimation tools that automatically assume every ETH transfer costs 21,000 gas could provide inaccurate estimates or fail altogether. Ethereum developers are encouraging projects to review and update their software before the upgrade reaches the main network.
The changes are part of a broader effort to improve Ethereum’s scalability and make the cost of storing permanent data on the network more accurately reflect its long-term impact. Operations such as creating accounts, deploying smart contracts, and adding new storage slots will become more expensive because they permanently increase Ethereum’s state size.
Earlier development discussions suggested that creating new accounts could become several times more expensive than today, while deploying smart contracts could see even larger increases in cost. Existing accounts and already-deployed contracts would not be affected in the same way.
Glamsterdam includes more than just gas repricing. The upgrade will also introduce enshrined proposer-builder separation (ePBS), a major change to how Ethereum blocks are built and validated. This aims to improve block production and strengthen the network’s infrastructure.
Another important feature is Block-Level Access Lists, which help nodes identify what data a block will need before processing it. This could improve efficiency and allow more parallel transaction execution in the future.
The upgrade will also raise contract size limits. Maximum deployed contract size will increase from 24 KiB to 64 KiB, while the limit for initialization code will rise from 48 KiB to 128 KiB, giving developers more flexibility when building complex applications.
Ethereum’s Platåberget testnet was launched specifically to give developers a longer testing period. Unlike previous short-lived development networks, it is expected to remain active for several months, allowing projects to identify bugs and compatibility issues before Glamsterdam eventually reaches Ethereum mainnet.
For now, the Ethereum Foundation’s main message is simple: any application that assumes gas costs are fixed should be tested and updated. While the 21,000-gas rule will still apply to many ETH transfers, it will no longer apply universally, making preparation essential before the network upgrade moves closer to production.
