Ethereum’s development team has locked in a timeline for the network’s next major upgrade. Glamsterdam is set to activate on the Sepolia testnet on October 6, marking an early milestone on the road toward a live rollout.
The Ethereum Foundation said on Monday that Sepolia node operators need to update both their execution-layer and consensus-layer clients ahead of the activation. According to the foundation, the upgrade is scheduled to go live at 13:53:36 UTC, coinciding with epoch 353,024 and slot 11,296,768. Dates for the Hoodi testnet and for mainnet have not been finalised, so the October 6 rollout applies only to Sepolia for now.
Glamsterdam brings several technical changes to the network. Among them is enshrined proposer-builder separation, which folds the handoff between specialized block builders and validators directly into Ethereum’s protocol rather than leaving it to outside middleware. The upgrade also adds block-level access lists, a feature that logs the accounts and storage locations touched during each block.
Gas pricing is getting an overhaul as well, with adjustments meant to better reflect the actual cost of creating and accessing data on the network. The foundation cautioned that contracts built around fixed gas stipends or hardcoded gas limits may need to be revised to work properly under the new system.
Broadly, Glamsterdam is meant to let Ethereum pack more activity into each block without placing excessive strain on the machines responsible for verifying it. The Sepolia activation follows closely on the heels of a large private rehearsal that wrapped up on September 17, in which the network pushed its block gas limit toward 200 million and completed the Glamsterdam transition without losing finality.
Developers have zeroed in on October 27 as a tentative date for the next public test, this time on the validator-focused Hoodi testnet. No timeline has been set yet for when Glamsterdam will reach Ethereum’s mainnet, leaving that decision for a later stage once testing on Sepolia and Hoodi provides more data on how the upgrade performs.
