Ethereum’s Biggest Upgrade Is Coming: Glamsterdam Testnet Goes Live

Ethereum has launched the Plataberget public testnet as developers begin testing the upcoming Glamsterdam upgrade. The network will serve as a public testing ground for major changes to Ethereum’s block building, gas rules, and data access system, with the Glamsterdam fork set for August 20, 2026.

Platberget Opens Glamsterdam Testing to the Public

The Ethereum Foundation announced Plataberget, calling it an early testing ground for Glamsterdam, a name combining the planned Gloas and Amsterdam upgrades. 

This gives developers, validators and other Ethereum users more time to test the changes before they move to longer running networks such as Sepolia and Hoodi.

The testnet is also permissionless, meaning validators, developers and other Ethereum users can join and test their systems before they move to longer running networks such as Sepolia and Hoodi.

The network is expected to use about 50,000 validators across roughly 50 nodes, with different client combinations being tested.

Ethereum’s 21,000 Gas Rule Is Also Changing

One of the most important changes for everyday users is the way Ethereum handles basic ETH transfers.

Transfers to existing accounts will still use 21,000 gas. However, sending ETH to a new account will require extra state gas because the transaction creates new data on Ethereum.

This change could affect wallets, gas estimators, and other tools that assume every ETH transfer has the same gas cost. Developers will need to update these systems before Glamsterdam reaches Ethereum’s mainnet.

Glamsterdam Brings Major Network Changes

Glamsterdam also includes several changes aimed at improving how Ethereum processes transactions.

ePBS will bring proposer-builder separation directly into Ethereum’s core rules. This could change how blocks are created and reduce reliance on external block-building systems.

BALs will record which parts of Ethereum’s state are accessed during block execution. The change is important for Ethereum’s longer-term plan to process more transactions at the same time.

The upgrade also raises the smart contract size limit from 24 KiB to 64 KiB. The maximum initcode size will rise from 48 KiB to 128 KiB.

Another set of gas changes is designed to support a higher gas floor of around 200 million, giving Ethereum more room to handle activity on the base layer.

What Comes After August 20?

Plataberget is not the final stop. Ethereum developers plan to move Glamsterdam testing toward longer-running networks such as Sepolia and Hoodi once the changes become stable. 

The mainnet upgrade is currently targeted for the second half of 2026, with ethereum.org listing Glamsterdam as a major 2026 upgrade.

The Ethereum Foundation has also said existing smart contracts are expected to keep working after Glamsterdam, although developers will need to review gas use and update tools that depend on older network rules.