Hoodi

Glamsterdam, the combined execution and consensus upgrade for Ethereum, will go live on the Hoodi test network on October 26, 2026, 20 days after it activated on Sepolia. Mainnet has no date, so ETH holders have nothing to do, but Hoodi stakers and node operators must update both of their clients first.

• Activation is at epoch 132,352, slot 4,235,264, at 17:42:48 UTC on October 26, 2026.
• Hoodi’s gas limit rises to 200M at the same epoch, matching the setting used on Sepolia.
• Mainnet has no date; client teams will announce it separately once they decide.

• 132,352 Hoodi activation epoch for Glamsterdam, slot 4,235,264
• 200M Hoodi gas limit after activation, matching Sepolia’s setting
• 20 days Gap between Sepolia activation (Oct 6) and Hoodi (Oct 26)

Ethereum developers have scheduled Glamsterdam to activate on the Hoodi testnet at epoch 132,352, slot 4,235,264, on October 26, 2026, according to the Ethereum Foundation’s announcement post. Hoodi is a public test network where stakers and developers rehearse protocol changes before they reach mainnet. Glamsterdam pairs the Amsterdam execution layer upgrade with the Gloas consensus layer upgrade.

Hoodi Activation Follows Sepolia’s October 6 Fork

Glamsterdam went live on Sepolia on October 6, 2026. Hoodi is next.

Node operators must update both execution and consensus clients before 17:42:48 UTC on October 26. Hoodi stakers must update the beacon node and the validator client, and review their client’s instructions for new ePBS duties and for configuring the gas limit their validators target after activation.

The post says Hoodi-compatible client versions “will be added to the client release tables as they are confirmed,” and tells operators to use only a release whose notes explicitly confirm support for the Hoodi activation.

A node that does not support the new rules cannot follow the upgraded network after activation.

Ethereum Foundation, Glamsterdam Hoodi Testnet Announcement

ePBS and Block Access Lists Change How Blocks Are Built and Checked

EIP-7732 writes proposer-builder separation into the consensus protocol. A proposer includes a builder’s commitment to an execution payload, the builder reveals the payload later, and the protocol handles payment to the proposer. A payload timeliness committee attests to whether the payload and its blob data arrived on time.

EIP-7928 adds enforced block-level access lists that record the accounts and storage locations a block touches, plus post-transaction state changes. Clients can use them to read state from disk in parallel, validate transactions in parallel and compute state roots more efficiently.

EIP-8037 Meters State Creation Separately

EIP-8037 raises the cost of creating state and meters it on its own. A companion change, EIP-8038, updates state-access costs, and further changes touch intrinsic transaction gas, calldata, access lists and block gas accounting.

The post warns that contracts relying on fixed gas stipends, hardcoded gas limits or assumptions about remaining gas “may need changes.” It points developers to a repricing impact guide for searching affected contracts.

What Hoodi Activation Means for Stakers, Builders and Contract Teams

Sepolia already ran the fork, so Hoodi adds a second environment where ePBS duties, the timeliness committee and the new gas rules meet a staking setup.

Builder operators carry the most workload. ePBS is meant to reduce reliance on “trusted middleware” between proposers and builders, which in current practice means relay infrastructure. Teams running external block-building setups need Glamsterdam-specific instructions, and the post says tooling guidance for Hoodi will be added once confirmed.

Contract teams have the clearest deadline. State creation will cost more under EIP-8037, and the post says to test gas estimation and gas-dependent logic on Sepolia and Hoodi.

What the Post Leaves Open

The post sets no mainnet date, and it names no criteria or testnet results that would trigger one, saying only that client teams will announce the time “once decided.” It does not give the new gas costs, so developers must pull those from the EIPs and the repricing guide.

The client release tables had no confirmed Hoodi versions in the text provided, and builder and validator tooling guidance is still pending.

The CCS read. We expect the gas repricing, not ePBS, to cause the most breakage. Validators and builders get client updates and documentation, while contracts with hardcoded gas assumptions fail in ways only their authors can find. Sepolia and Hoodi are the two places to find them before mainnet gets a date, and teams that wait for that date will have the least time to fix them.

Next: Glamsterdam activates on Hoodi at 17:42:48 UTC on Monday, October 26, 2026, and client teams still have to publish confirmed Hoodi release versions and, later, a mainnet activation time.