Ethereum Sets Glamsterdam Upgrade for Hoodi Testnet on Oct. 26

What activates on Hoodi

The Hoodi deployment follows Glamsterdam’s Sepolia activation on Oct. 6, which took place at epoch 353,024, slot 11,296,768. For Hoodi, the same announcement says the network’s gas limit will also be raised to 200 million at the activation epoch, matching the Sepolia configuration.

Ethereum said this Hoodi notice does not schedule a mainnet upgrade. Client teams are expected to announce a mainnet date separately once it is decided.

Core protocol changes in Glamsterdam

The most prominent changes in Glamsterdam are enshrined proposer-builder separation, or ePBS, and block-level access lists, known as BALs. Ethereum describes both as building blocks for higher execution throughput on layer 1 while keeping block validation manageable for node operators.

Under EIP-7732, proposer-builder separation moves the relationship between block proposers and builders into the protocol itself. A proposer includes a builder’s commitment to an execution payload, and the builder then reveals that payload later. The protocol also handles payment to the proposer, which Ethereum says reduces reliance on trusted middleware.

EIP-7928 adds enforced block-level access lists that capture which accounts and storage locations were touched during a block, along with post-transaction state changes. The stated goal is to let clients parallelize state reads and transaction validation and to compute state roots more efficiently.

Gas repricing and developer impact

Glamsterdam also revises gas accounting to better match resource consumption and state growth. The announcement highlights EIP-8037, which increases and separately meters the cost of creating state, and EIP-8038, which updates state-access costs. Other scheduled changes affect intrinsic transaction gas, calldata, access lists, and block gas accounting.

Ethereum said application developers should test contracts and gas estimation logic against the new rules. Projects that depend on fixed gas stipends, hardcoded gas limits, or assumptions about remaining gas may need updates after the repricing changes.

Operator preparation and included EIPs

Node operators on Hoodi are required to update both execution-layer and consensus-layer clients before activation. The Ethereum Foundation said Hoodi-compatible releases will continue to be added to its client tables as they are confirmed, and only versions whose release notes explicitly support the scheduled Hoodi activation should be used.

The scheduled Glamsterdam package spans a broad list of EIPs beyond ePBS and BALs. The set includes ETH transfer logs, a slot-number opcode, a higher maximum contract size, a deterministic factory contract, new stack-manipulation instructions, forward-compatible consensus data structures, exclusion of slashed validators from proposing, and increased exit and consolidation churn.

Next confirmed step

For now, the next confirmed milestone is Hoodi’s activation on Oct. 26. Ethereum said validator operators and teams running builder infrastructure should review the new ePBS duties and interfaces, while application and tooling developers are expected to test on Sepolia and Hoodi after activation.

No action is required on Ethereum mainnet as a result of this testnet announcement alone. Mainnet timing, along with compatible client releases for that rollout, will be announced separately once client teams make a decision.