Not financial advice. This article is for informational purposes only.
Ethereum’s next hard fork is one testnet away from a mainnet decision. The Ethereum Foundation confirmed on Oct. 16 that Glamsterdam will activate on the Hoodi testnet at epoch 132,352 (slot 4,235,264) on Oct. 26, 2026, at 17:42:48 UTC, following its Sepolia activation on Oct. 6. The upgrade adds enshrined proposer-builder separation (ePBS, EIP-7732), block-level access lists (EIP-7928), and gas-pricing changes meant to better reflect the cost of execution and state growth. Hoodi’s gas limit rises to 200 million at the fork. The mainnet activation date has not been decided. Here’s what node operators, builders, and dapp developers need to do, and what to watch next.
The schedule
| Network | Epoch | Slot | UTC time |
|---|---|---|---|
| Sepolia | 353,024 | 11,296,768 | 2026-10-06 13:53:36 (activated) |
| Hoodi | 132,352 | 4,235,264 | 2026-10-26 17:42:48 |
| Mainnet | TBD | TBD | TBD |
Per the EF announcement, the mainnet time “will be announced once decided by client teams,” and a separate announcement will cover it. Ethereum.org’s Glamsterdam page lists mainnet as expected in Q4 2026, with the date not yet confirmed. Core developers kept the Oct. 26 Hoodi target on the Oct. 15 All Core Devs Consensus call, according to EtherWorld’s recap.
What’s in Glamsterdam
The name combines Amsterdam (the execution-layer upgrade) and Gloas (the consensus-layer upgrade). Headline changes:
- Enshrined proposer-builder separation (EIP-7732). A proposer commits to a builder’s execution payload, and the builder reveals it afterward. The protocol handles the payment to the proposer, which reduces reliance on trusted middleware. A payload timeliness committee attests to whether the payload and its blob data showed up on time.
- Block-level access lists (EIP-7928). Blocks record the accounts and storage slots they touch, so clients can read state and validate transactions in parallel.
- Gas repricing. EIP-8037 raises and separately meters the cost of creating state, and EIP-8038 updates state-access costs. Other changes touch intrinsic transaction gas (EIP-2780), the calldata floor (EIP-7976), access-list costs (EIP-7981), and block gas accounting without refunds (EIP-7778).
- Developer extras. ETH transfers emit logs (EIP-7708), a SLOTNUM opcode (EIP-7843), a higher maximum contract size (EIP-7954), a deterministic factory contract (EIP-7997), and new stack instructions (EIP-8024).
The full list is tracked in the meta-EIP, EIP-7773, which also covers consensus changes such as excluding slashed validators from proposing (EIP-8045) and higher exit and consolidation churn (EIP-8061).
How Sepolia went
CoinDesk reported on Oct. 8 that, after the fork, Sepolia blocks were running near a 200 million gas limit, up from about 60 million, with 26% to 46% utilization in a 25-block sample. Treat that as a snapshot of a testnet, not a forecast for mainnet.
Who needs to act
- Hoodi stakers: update both the execution and consensus clients, and update both the beacon node and the validator client. Review your client’s instructions for the new ePBS duties, any builder/MEV tooling changes, and the gas limit your validators target after activation.
- Non-staking Hoodi node operators: upgrade both clients before Oct. 26, 17:42:48 UTC.
- Mainnet users and ETH holders: nothing to do yet. This announcement covers Hoodi only.
- App developers: retest contracts and gas estimation. Contracts that rely on fixed gas stipends, hardcoded gas limits, or assumptions about remaining gas may need changes. The EF points to a Glamsterdam repricing impact guide.
Client releases
The EF’s release tables are being filled in as teams confirm Hoodi support, and you should only run a release whose notes explicitly confirm the Hoodi activation. As of Oct. 17, the tables list Lodestar 1.50.0, Nimbus 26.10.1, Prysm v7.3.0, and Teku 26.10.1 on the consensus side, and Besu 26.10.0, Ethrex 30.0.0-rc.2, and Nethermind 2.2.0 on the execution side. Grandine, Lighthouse, Erigon, go-ethereum, and Reth were still blank. Check the announcement for the latest before upgrading.
What to watch
- Fork health on Hoodi on Oct. 26 (finality, missed slots, builder participation)
- The remaining client releases in the EF tables
- The next All Core Devs calls, where a mainnet slot would be chosen
- A separate EF mainnet announcement. Until that’s published, any December date you see is a proposal, not a schedule.
Sources
- Ethereum Foundation, “Glamsterdam Hoodi Testnet Announcement” (Oct. 16, 2026)
- ethereum.org, Glamsterdam roadmap page
- CoinDesk, Sepolia near 200 million gas per block (Oct. 8, 2026)
- EtherWorld, ACDC #189 recap (Oct. 15, 2026)
Not financial advice. This article is for informational purposes only.
