Ethereum's Glamsterdam upgrade set for Sepolia testnet on Oct. 6, mainnet date still open

Ethereum's next network upgrade, Glamsterdam, is moving to public testnets. The Ethereum Foundation (EF) said in a Sept. 28 blog post that the upgrade will activate on the Sepolia testnet at 10:53:36 p.m. KST on Oct. 6 (13:53:36 UTC, epoch 353,024). Testnets are trial networks where no real money changes hands, used to check changes before they reach mainnet.

Nothing scheduled after Sepolia yet

"Hoodi and mainnet activation dates have not yet been decided," the foundation said in the announcement. The schedule the foundation has published, and the status of each step, is as follows.

Introducing Platåberget on Aug. 17, the foundation said, "Unlike the short-lived devnets before it, Platåberget is intended to run for a few months," and laid out a path through the Sepolia and Hoodi testnets to mainnet. The previous upgrade, Fusaka, went through several testnets before activating on mainnet on Dec. 4, 2025 (KST).

New rules between builders and validators

Glamsterdam combines Amsterdam, the upgrade to the execution layer that processes transactions, with Gloas, the upgrade to the consensus layer. According to the foundation, execution-layer upgrades are named after Devcon and Devconnect host cities and consensus-layer upgrades after stars; Amsterdam hosted Devconnect in 2022. The upgrade bundles 18 core EIPs (Ethereum Improvement Proposals) plus seven networking and supporting EIPs.

• Enshrined proposer-builder separation (ePBS, EIP-7732): Today, outside middleware connects the "builders" who assemble block contents with the validators who propose blocks. This change writes that separation of roles into Ethereum's own protocol rules.
• Block-level access lists (BAL, EIP-7928): Blocks record in advance which accounts and storage slots their transactions touch, laying the groundwork for nodes to validate multiple transactions in parallel.
• Other changes: These include logs for ETH transfers (EIP-7708), a higher maximum contract size (EIP-7954), preventing slashed validators from proposing blocks (EIP-8045) and higher limits on validator exit and consolidation processing (EIP-8061).

First state gas repricing since Berlin

The foundation said the gas repricing touches every wallet, indexer and gas-estimation tool, giving it a broader impact than ePBS. EIP-8037 raises the cost of creating new accounts, storage and code, while EIP-8038 raises the cost of reading and writing storage. "Gas prices for state operations were last adjusted in the Berlin fork in 2021," the foundation wrote in a separate Aug. 24 post, adding that Ethereum's state has grown significantly since then and that repricing is needed before the gas limit can be raised further.

The foundation warned that contracts with hardcoded gas values, such as those forwarding a fixed 2,300-gas stipend on transfers, and presigned transactions with fixed gas limits may fail. It advised application developers to review the affected EIPs and test after the Sepolia activation, and told builders of wallets and gas-estimation tools to update their estimation logic for the new gas schedule. Regular users need to take no action because wallets and infrastructure handle the changes, it said.

Node operators must upgrade before Oct. 6

Sepolia node operators must upgrade both their execution and consensus clients before activation, and stakers must update both their beacon nodes and validator clients. Compatible versions published by the foundation include, on the execution layer, Geth (go-ethereum) 1.17.6, Besu 26.9.0, Nethermind 2.0.0, Reth 2.7.0 and Erigon 3.7.0, and on the consensus layer, Prysm 7.2.0, Teku 26.9.1 and Lodestar 1.49.0. The foundation separately noted that Prysm 7.2.0 defaults to a 60 million gas limit after activation.

Because the announcement covers Sepolia only, mainnet users and ETH holders have nothing to do, and mainnet activation will be announced separately, the foundation said. In South Korea, ETH trades on the Korean won markets of the local exchanges Upbit and Bithumb. As of 11:36 p.m. KST on Sept. 29, ETH was priced at 3,664,000 won on Upbit and 3,668,000 won on Bithumb.