Ethereum sets H1 2026 Glamsterdam plan: ePBS, BALs

Glamsterdam H1 2026: Ethereum’s next upgrade and target date

According to the ethereum foundation’s 2026 protocol priorities update, Glamsterdam is targeted for the first half of 2026, with work organized across three tracks: Scale, Improve UX, and Harden the L1 (the Scale track includes enshrined proposer–builder separation, gas-limit evaluations, and blob scaling) (blog.ethereum.org).

The update positions Glamsterdam as the next mainnet upgrade, with Hegota slated to follow later in the year, subject to client readiness and testing milestones. Scope remains under discussion, and inclusion of any given feature will depend on test results and security review.

Why it matters: enshrined PBS (ePBS), Block-Level Access Lists (BALs), gas limits

Enshrined PBS (ePBS) would move the proposer–builder separation into the protocol, aiming to reduce reliance on external relays and to harden censorship resistance by making block-builder markets more trust-minimized. If implemented, this could standardize MEV flows while narrowing opportunities for discretionary transaction filtering.

Block-Level Access Lists (BALs) are discussed as a way to preload needed state for a block so nodes avoid repeated disk reads, which can be a major execution bottleneck. According to Gabriel Trintinalia, a senior engineer at Consensys, this approach targets lower I/O overhead and more predictable performance for validators and full nodes.

On capacity, Gary Schulte has predicted that a gas-limit increase to 100 million is plausible in H1 2026, with a potential doubling later if ePBS lands and client performance supports it, as reported by Cointelegraph (cointelegraph.com).

Framing the intent behind these priorities, vitalik buterin has argued for renewing Ethereum’s trust-minimized ethos in the year ahead: “2026 [should] be the year Ethereum ‘takes back lost ground in terms of self-sovereignty and trustlessness,’” as reported by CryptoNews (cryptonews.com).

Immediate impact for users, developers, and Ethereum L2s

For users, there is no immediate change until Glamsterdam activates on mainnet. If ePBS ships, inclusion reliability could improve and censorship risk could decline, though realized fee effects will depend on demand and post-fork measurements.

For developers, the largest lift sits in client and engine-API updates, interoperability testing, and performance validation under higher load. Application teams could see more predictable inclusion and potential latency improvements if BALs ease execution bottlenecks.

For Ethereum L2s, L1 upgrades that expand throughput and harden neutrality may reduce pressure to centralize scaling at the edges. Rollups likely remain central, but specializations, settlement, privacy, or app-specific throughput, may become more pronounced as L1 capacity grows.

At the time of writing, Ethereum traded at $1,945.31, down 2.7% over the past day, providing neutral market context as Glamsterdam planning progresses, as reported by Meyka (meyka.com).

Risks, dependencies, and timeline to watch

ePBS risks: Free Option Problem, engine-API changes, client readiness

Researchers have highlighted the “Free Option Problem,” where builders can opportunistically skip payloads in favor of empty blocks during volatile MEV conditions; mitigations under study include narrower decision windows and targeted penalties (arXiv.org).

Developer updates have also flagged testing bottlenecks and consensus–execution coordination as areas of uncertainty, with BALs further along than ePBS and engine-API changes still being worked through, as reported by CryptoNews.net (cryptonews.net).

Roadmap links: Fusaka before Glamsterdam; Hegota after; scope/testing

Fusaka precedes Glamsterdam, and slippage there could cascade into later milestones; co-executive director Tomasz K. Stańczak has stressed the need to protect that schedule to maintain roadmap confidence, as reported by The Block (theblock.co).

Given these dependencies and the depth of ePBS changes, a reduced-scope fork remains possible if testing surfaces unresolved risks, with follow-on features deferred to Hegota after sufficient validation.

FAQ about Glamsterdam upgrade

Which features are expected in Glamsterdam (ePBS, BALs, gas limit changes) and why do they matter?

Developer discussions center on ePBS and BALs, plus potential gas-limit increases. They aim to harden censorship resistance, raise throughput, and improve node performance.

How could ePBS and BALs affect gas fees, throughput, and MEV/censorship risk on Ethereum?

ePBS may curb censorship and streamline MEV markets; BALs can lower execution overhead, supporting throughput. Fee outcomes hinge on gas limits, demand, and measured post-fork data.