Ethereum Glamsterdam on Sepolia: What 200M Gas Means Next

Ethereum's next major network upgrade, Glamsterdam, is now running on the Sepolia testnet, and the early numbers show why developers are excited. The upgrade activated on Sepolia on October 6, 2026, and blocks there now carry a gas limit of nearly 200 million, more than three times the 60 million limit on Ethereum mainnet today. For anyone watching Ethereum's scaling roadmap, this is the first time Glamsterdam's core changes are running together on a public network.

• Activation: Glamsterdam went live on Sepolia on October 6, 2026 at 13:53:36 UTC, at epoch 353,024, per the Ethereum Foundation.
• Headline changes: EIP-7732 (enshrined proposer-builder separation) and EIP-7928 (block-level access lists for parallel validation).
• Capacity: Sepolia blocks carry a gas limit of nearly 200 million versus 60 million on mainnet; blocks sampled by Decrypt used about 24% to 43% of it.
• Next steps: Hoodi testnet and mainnet dates are not yet set, and ETH holders do not need to take any action.

What Does Glamsterdam Change for Ethereum?

The Ethereum Foundation highlights two headline improvements. EIP-7732, enshrined proposer-builder separation (ePBS), moves the exchange between block proposers and block builders into the protocol itself. Today much of that handoff relies on trusted third-party relays. Building it into Ethereum reduces that dependency and gives validators more time to check execution payloads.

EIP-7928, block-level access lists, records which accounts and storage slots a block touches. With that map in hand, clients can read state and validate transactions in parallel rather than strictly one after another. Parallel processing is one of the main levers for raising throughput without demanding much more powerful hardware from node operators.

Glamsterdam also bundles a set of smaller improvements, including logs for plain ETH transfers (EIP-7708), a new SLOTNUM opcode (EIP-7843), a higher maximum contract size (EIP-7954), and gas repricing for state creation and access (EIP-8037 and EIP-8038).

How Much More Capacity Could Ethereum Get?

Decrypt checked a run of Sepolia blocks on October 8 and found them using roughly 47.1 million to 85.9 million gas, between about 24% and 43% of the new ceiling. That is already more than mainnet blocks can hold today. For context, mainnet's limit rose from 30 million to 60 million through 2025, and developers have discussed moving toward roughly 200 million after Glamsterdam, according to Decrypt.

There is a sensible safety valve here. The Ethereum Foundation notes that the Prysm and Teku consensus clients default to a 60 million gas limit after activation, so validators who want to signal for 200 million must set it explicitly. Capacity increases on Ethereum remain a validator choice rather than something forced by a single release.

When Will Glamsterdam Reach Ethereum Mainnet?

Not yet. The Ethereum Foundation says activation dates for the Hoodi testnet and mainnet have not been set, and this announcement only covers Sepolia. Testnets exist precisely so client teams, stakers and app developers can shake out issues first, and the Ethereum Bug Bounty Program now covers the Glamsterdam specifications to encourage researchers to dig in.

Updated releases are available from all major clients, including go-ethereum 1.17.7, Nethermind 2.1.0, Reth 2.7.0, Lighthouse 8.3.0-rc.0, Prysm 7.2.1 and Teku 26.9.1. Developers are encouraged to test contracts on Sepolia, especially any that rely on fixed gas assumptions, since the repricing EIPs change some costs.

What It Means for Users and Builders

For ordinary ETH holders, nothing changes today, and no action is needed. For builders, Glamsterdam on Sepolia is the moment to start testing. We first looked at the plan back in March in our explainer on Glamsterdam's parallel processing and enshrined PBS; seeing those ideas running on a public testnet is real progress toward a faster, cheaper Ethereum. This is technology news, not investment advice. More in our crypto coverage.

Sources: Ethereum Foundation Blog — Glamsterdam Testnet Announcement — September 28, 2026; Decrypt — Ethereum test raises block limit to 3x current capacity — October 8, 2026.