Ethereum's Glamsterdam hard fork — the largest protocol overhaul since The Merge — reached final devnet testing in June 2026 and targets mainnet activation in Q3 2026, with an internal working date near the end of August. The fork ships ten Ethereum Improvement Proposals tracked under Meta EIP-77...
"ePBS ensures that block builder centralization does not creep into staking centralization, but it leaves the question: what do we do about block builder centralization? And what are the other problems in the block building pipeline that need to be addressed, and how?" — Vitalik Buterin, Ethereum Co-Founder
Ethereum's Glamsterdam hard fork — the largest protocol overhaul since The Merge — reached final devnet testing in June 2026 and targets mainnet activation in Q3 2026, with an internal working date near the end of August. The fork ships ten Ethereum Improvement Proposals tracked under Meta EIP-7773, headlined by EIP-7732 (Enshrined Proposer-Builder Separation) and EIP-7928 (Block-Level Access Lists). Together, these changes move block construction into the protocol layer, eliminate dependency on external relay infrastructure, and lay the groundwork for parallel transaction execution.
The practical implications are measurable. The gas limit is set to rise from 60 million to 200 million per block via validator signaling, targeting approximately 10,000 transactions per second under realistic workloads — roughly 3x current L1 capacity. Standard ETH transfers are projected to become up to 71% cheaper. For Layer 2 rollups, blob capacity targets a 24x increase from current levels, pushing per-transaction settlement costs below $0.02 on some networks.
The upgrade arrives against a backdrop of institutional concern. The Ethereum Foundation's Client Incentive Program expired in April 2026 with no replacement. Eight senior researchers departed the Foundation in 2026, including protocol coordinators Tim Beiko and Barnabé Monnot. Former EF contributor Trent Van Epps has warned that core developer funding could face a shortfall within three to nine months.
Glamsterdam is Ethereum's first hard fork targeting base-layer throughput since The Merge in September 2022. Where previous upgrades — Shapella, Dencun, and Fusaka — focused on withdrawals, blob data availability, and consensus refinements respectively, Glamsterdam rewrites how Ethereum builds, prices, and validates blocks at the protocol level.
The upgrade bundles ten EIPs under the Glamsterdam Meta EIP-7773, currently in Draft status as of June 17, 2026. The scope is not yet immutable, but the core proposals have survived multiple rounds of All Core Devs calls and cross-client testing on the Soldøgn interop devnet, which concluded on May 2, 2026.
The strategic intent is explicit: scale Ethereum's own Layer 1 again, rather than outsourcing all throughput to rollups. This represents a directional shift from the rollup-centric roadmap that dominated 2023-2025.
EIP-7732 formalizes the separation of block proposers (validators who select the consensus block) from builders (entities that assemble the execution payload) directly within the Ethereum protocol. This role division already exists in practice through MEV-Boost, Flashbots' external relay system, but currently depends on trusted third-party infrastructure.
The dependency is substantial. According to data tracked by The Block, MEV-Boost relays handle approximately 92% of Ethereum blocks. Only eight active relays operate, and the five largest hold over 90% market share. This concentration creates a centralization chokepoint — relays can censor blocks by declining to relay transactions interacting with sanctioned addresses.
ePBS eliminates the relay intermediary. Onchain builders become permissionless participants who meet an ETH collateral requirement and operate within the protocol's auction mechanism. The upgrade introduces the Payload Timeliness Committee (PTC), a new validator duty that verifies builders reveal block contents on time. This dual-deadline logic — validators attest to the consensus block and the execution payload timeliness separately — expands the data propagation window from approximately 2 seconds to roughly 9 seconds.
The expanded window is not merely an efficiency gain. It unblocks Ethereum's capacity to handle larger blocks without degraded propagation, which is a prerequisite for the gas limit increases that follow.
EIP-7928 introduces Block-Level Access Lists (BALs), a mechanism that allows blocks to declare in advance which accounts and smart-contract storage slots they will access during execution. This acts as a pre-execution map for the network.
The functional consequence: because BALs expose which transactions do not overlap in state access, nodes can perform parallel disk reads, fetching data for multiple transactions simultaneously rather than sequentially. Unrelated transactions can be grouped and processed in parallel.
This is not parallel execution in the full sense — Ethereum does not yet execute transactions concurrently at the EVM level — but it eliminates the serial I/O bottleneck that currently constrains throughput. The practical effect enables Ethereum clients to preload data more efficiently, making block execution faster, more predictable, and easier to optimize.
Combined with ePBS, BALs clear the path for validators to safely signal a gas limit increase from the current 60 million range toward 200 million per block. The 200 million target is a design goal, not a value the fork enforces. Validators set the limit via standard gas-vote signaling and would increase it incrementally as nodes demonstrate they can handle larger blocks.
The ten scheduled EIPs as of June 17, 2026, are: EIP-7708, EIP-7732, EIP-7778, EIP-7843, EIP-7928, EIP-7954, EIP-7976, EIP-7981, EIP-8024, and EIP-8037. Beyond the two headline proposals:
The most immediately visible change is cost reduction. Gas repricing proposals cut the intrinsic transaction-gas floor, projected to make standard ETH transfers between existing accounts up to 71% cheaper. Across both simple transfers and complex smart contract interactions, the upgrade targets a 78.6% reduction in gas fees.
These projections assume the gas limit rises to 200 million as intended. At the current 60 million limit, the fee reduction still applies per transaction, but the network's capacity constraint remains unchanged. The full economic benefit requires validators to coordinate the gas-limit increase post-fork.
For context, Ethereum's L1 already reached all-time high daily transaction counts following the Fusaka upgrade in December 2025, while fees simultaneously declined. Glamsterdam extends this trajectory.
Glamsterdam's capacity expansion directly affects L2 rollup economics. Blob capacity — the data bandwidth available for rollups to post transaction batches to Ethereum — targets an increase to 72+ blobs per block, a 24x expansion from the initial EIP-4844 launch parameters.
Current blob settlement costs vary by network: approximately $0.012 per transaction on Linea, $0.018 on Arbitrum, a 33% differential relevant for high-frequency DeFi applications. Industry estimates suggest blob fees could contribute 30-50% of total ETH burn by 2026, depending on L2 activity scaling.
A typical L2 transaction that cost approximately $0.50 in late 2025 dropped to $0.20-$0.30 following Fusaka. Further reductions are expected as Glamsterdam expands blob capacity. This creates a dual dynamic: L2 transactions become cheaper, but the volume increase could offset per-unit fee declines in total ETH burned — a critical metric for ETH's deflationary mechanics.
Glamsterdam does not directly alter Ethereum's base issuance rate, but the structural changes affect total validator income through three channels.
First, ePBS replaces the current relay-mediated MEV auction with a transparent, protocol-native mechanism. This may reduce friction costs in MEV extraction, increasing the net amount flowing to stakers versus intermediaries. The magnitude depends on how the builder market reprices under the new architecture.
Second, faster exit processing reduces time-to-liquidity risk. According to Figment, one of the largest institutional staking operators, the exit queue improvement is "one of the more operationally consequential changes" for institutional clients who price staking positions based partly on exit delay.
Third, the gas limit expansion increases total block space available, which at sustained demand levels translates to higher aggregate fee revenue per block. Whether this materializes depends on L1 demand growth — a variable that the upgrade itself aims to stimulate through lower per-transaction costs.
Validators face new operational requirements. Both execution and consensus clients must be updated to handle ePBS mechanics. Node operators joining the Payload Timeliness Committee take on the new duty of verifying builder payload delivery. Non-compliant validators risk attestation penalties.
| Milestone | Date | Status | |-----------|------|--------| | Soldøgn interop devnet | May 2, 2026 | Completed | | Final devnet (multi-client) | Mid-June 2026 | Active | | Public testnets (Holesky, Hoodi) | TBD | Pending | | Mainnet activation (internal target) | Late August 2026 | Aspirational | | Mainnet activation (realistic range) | Sept–Dec 2026 | Estimated |
Three factors could push activation into Q4 2026 or later. ePBS implementation complexity across multiple client teams is the primary concern — cross-client parity has historically been the bottleneck in Ethereum upgrades. Gas repricing implementation requires careful calibration to avoid unintended economic effects. And public testnet seasoning typically runs two to four months based on precedent from prior forks.
The Meta EIP-7773 remains in Draft status, meaning the proposal set could still change. However, the core ePBS and BAL proposals are considered locked by the All Core Devs process.
Glamsterdam's technical ambition arrives alongside institutional fragility in Ethereum's governance layer. The Ethereum Foundation's Client Incentive Program, a staking-reward-based initiative that funded execution and consensus client teams since December 2021, expired in April 2026 with no announced replacement.
Eight senior researchers departed the Foundation in 2026, five in May alone. Tim Beiko and Barnabé Monnot, two of the most prominent figures in core protocol coordination, have stepped back. Former EF contributor Trent Van Epps warned in June 2026 that core developer funding could face a shortfall within three to nine months.
The Foundation's stated "Subtraction" philosophy — deliberately shrinking its own relative influence — has not clearly defined which external entities should absorb the responsibilities it relinquishes. Protocol Guild, a funding mechanism for core developers outside EF grants, exists but has not scaled to fill the gap left by the CIP's expiration.
Whether Glamsterdam ships on schedule depends partly on whether the coordination infrastructure survives the personnel turnover. The technical work on devnets continues, but the organizational scaffolding around it is under strain.
Glamsterdam represents Ethereum's most consequential technical bet since the transition to proof-of-stake. The fork addresses structural limitations — relay centralization, serial execution, gas pricing legacy overhead — that have constrained L1 capacity while the network's competitive position eroded to faster alternatives.
The technical scope is ambitious but grounded in concrete engineering. ePBS removes a trust assumption that affects 92% of block production. Block-Level Access Lists unlock parallelism without requiring a full EVM redesign. Gas repricing eliminates pricing artifacts that date to 2015.
The open question is execution risk — not technical, but organizational. Ethereum's core development coordination is under pressure from funding gaps and personnel departures at the Foundation level. The code is progressing through devnets. Whether the organizational infrastructure holds long enough to ship it is the variable the market is pricing.