Ethereum’s Glamsterdam upgrade launches on Sepolia testnet

What happened

Ethereum’s Glamsterdam upgrade has gone live on the Sepolia testnet, in one of the final major rehearsals before its mainnet activation. Glamsterdam went live on Sepolia on Tuesday at 1:53 pm UTC, Ethereum community contributor Pooja Ranjan announced in an X post .

The upgrade aims to advance Ethereum’s layer-1 scaling roadmap with enshrined proposer-builder separation, block-level access lists and changes to gas pricing that better reflect the cost of execution, the Ethereum Foundation announced in a Sept. The development marks one of the final testnet launches for Glamsterdam, arguably one of the most consequential upgrades of 2026, aiming to make the Ethereum network more scalable and efficient.

Source: Ethereum.org Aiming to improve Ethereum’s efficiency and scalability Glamsterdam marks the next major upgrade after Fusaka, designed to improve scalability , harden the layer-1 and make the network easier to use. Sepolia marks one of the final major rehearsals before the final activation of Glamsterdam, aimed at bringing more efficiency and scalability to the Ethereum mainnet. Currently, Ethereum is running in single-lane mode, processing transactions in a single order.