Ethereum's Glamsterdam hits last testnet on 26 Oct: what changes

Ethereum's next major upgrade, Glamsterdam, is scheduled to go live on the Hoodi test network on 26 October 2026 at 17:42:48 UTC, the Ethereum Foundation said in a Hoodi announcement. Hoodi is the last public testnet before mainnet, so a smooth run there clears the way for client teams to pick a mainnet date. Here are the five things to know.

It is the final dress rehearsal

Glamsterdam has already activated on the Sepolia testnet. Hoodi switches over at epoch 132,352 (slot 4,235,264). The Foundation stresses that this announcement covers Hoodi only and does not schedule a mainnet upgrade — that date and the matching client releases will be announced separately once client developers agree on it. The name combines Gloas (the consensus-layer upgrade, named after a star) and Amsterdam, the host city of Devconnect 2022.

Block builders become part of the protocol

The headline change is enshrined proposer-builder separation (ePBS, EIP-7732). Today most Ethereum blocks are assembled by specialised builders and passed to validators through third-party relays. ePBS brings that hand-off into the protocol itself, reducing reliance on those middlemen. Stakers will have new duties to review in their client's upgrade notes. (New to staking? Our proof-of-work vs proof-of-stake guide explains the basics.)

Blocks that are easier to process in parallel

Block-level access lists (EIP-7928) make each block declare which accounts and storage slots it touches. With that map in hand, clients can load data and execute transactions more efficiently — groundwork for handling more activity per block.

New gas prices and a 200M gas limit on testnets

A cluster of EIPs reprices operations to better reflect what they cost the network, including higher costs for creating new state (EIP-8037), state access (EIP-8038), calldata (EIP-7976) and access lists (EIP-7981). At activation, Hoodi's gas limit rises to 200 million, matching Sepolia. Ethereum researcher Toni Wahrstätter said on X that on mainnet this would mean going from 60 million to 200 million, roughly 3.3 times more room per block, and called 300 million a realistic next step — a personal view, not part of the upgrade. Developers are asked to check contracts that assume fixed gas costs.

Who needs to act

• ETH holders and mainnet users: nothing to do.
• Hoodi node operators and stakers: update both the execution and consensus clients (beacon node and validator client) before 26 October.
• App and tooling developers: test on Sepolia and Hoodi, and review changes to gas accounting, logs (ETH transfers will now emit a log under EIP-7708), opcodes and the larger maximum contract size (EIP-7954).

For background on how the network itself works, read our explainer What is Ethereum?.