Ethereum Sets Hoodi Glamsterdam Test for Oct. 26

Ethereum will activate the Glamsterdam upgrade on its Hoodi testnet on Oct. 26, 2026, at 17:42:48 UTC. The Ethereum Foundation announced the schedule on Oct. 16, giving Hoodi operators a deadline to update their software. The upgrade was activated on Sepolia, another Ethereum testnet, on Oct. 6.

Hoodi operators must update their execution and consensus clients before the activation. Validators must update their beacon node and validator client and review new validator duties, builder-tool compatibility and gas-limit settings.

The planned 200 million-gas target represents the amount of computational work intended for each block. It guides client defaults and operator recommendations. The actual block limit will adjust gradually through Ethereum’s existing rules, so the target will not immediately create a fixed limit for every block.

Transaction throughput will depend on the complexity of transactions included in each block. Network demand will continue to affect fees. The Foundation advises developers to test gas estimation and smart contracts because changes to gas pricing could affect contracts that use fixed stipends, hardcoded limits or assumptions about remaining gas.

Glamsterdam includes changes to Ethereum’s execution and consensus layers. Amsterdam, the execution-layer component, adds block-level access lists that record the accounts, storage and state changes used while processing a block. Gloas, the consensus-layer component, includes enshrined proposer-builder separation. This places the exchange between block proposers and builders within the protocol and gives validators more time to check execution.

The Foundation’s confirmed Hoodi releases include Besu 26.10.0, ethrex 30.0.0-rc.2 and Nethermind 2.2.0 for the execution layer. The listed consensus-layer releases are Lodestar 1.50.0, Nimbus 26.10.1, Prysm v7.3.0 and Teku 26.10.1. Ethrex’s listed version is a release candidate. Grandine, Lighthouse, Erigon, go-ethereum and Reth were not listed, so their operators should use releases whose notes confirm support for the Hoodi activation.

Besu 26.10.0 migrates Bonsai code storage during its first startup and retains more history when pruning. Operators that need to downgrade must first use Besu’s documented storage revert-code-format command before an older version can reopen the database.

The Hoodi announcement does not require action from Ethereum mainnet users, ETH holders or mainnet operators. The date for Glamsterdam’s mainnet activation remains undecided.