Ethereum's next hard fork, Glamsterdam, entered public testnet on August 17 when the Ethereum Foundation launched Platåberget. The fork activated on that testnet on August 20. Mainnet activation is targeted for Q4 2026, delayed from an original H1 2026 window. Ten Ethereum Improvement Proposals s...
Ethereum's next hard fork, Glamsterdam, entered public testnet on August 17 when the Ethereum Foundation launched Platåberget. The fork activated on that testnet on August 20. Mainnet activation is targeted for Q4 2026, delayed from an original H1 2026 window. Ten Ethereum Improvement Proposals ship under the Meta EIP-7773 umbrella, with two headline changes: EIP-7732 (Enshrined Proposer-Builder Separation) and EIP-7928 (Block-Level Access Lists).
The upgrade restructures how Ethereum builds, proposes, and validates blocks. It replaces the off-chain MEV-Boost relay infrastructure that currently handles approximately 88% of Ethereum blocks with an in-protocol mechanism. Simultaneously, Block-Level Access Lists pre-declare state access per transaction, enabling nodes to execute unrelated transactions in parallel. Together, these changes lay the groundwork for a gas limit increase from approximately 60 million to a 200 million target — a 3.33x capacity expansion that would push base-layer throughput toward 10,000 transactions per second, up from roughly 1,000 today.
Core developer Nixo Jayanthi described Glamsterdam as "probably the largest fork we've had since the Merge," adding that it will "change a lot of assumptions about Ethereum and set us up for much more scaling in the future." The upgrade follows Fusaka (December 2025), which introduced PeerDAS and raised the gas limit to 60 million.
The Ethereum Foundation announced the Platåberget testnet on August 17, 2026, with the Glamsterdam fork activating on August 20. Platåberget is a short-term public testnet designed to run for several months, giving developers and infrastructure operators a controlled environment to test post-Glamsterdam behavior before the upgrade reaches the longer-lived Sepolia and Hoodi testnets.
Timeline progression:
| Milestone | Date/Status | |---|---| | Soldøgn interop devnet concluded | May 2, 2026 | | Platåberget testnet launch | August 17, 2026 | | Glamsterdam fork on Platåberget | August 20, 2026 | | Non-finality devnet | Within one month of Platåberget feedback | | Sepolia and Hoodi upgrades | TBD | | Mainnet activation | Q4 2026 (target) |
The delay from H1 to Q4 2026 stems from the upgrade's expanded scope. All six major consensus clients (Lighthouse, Lodestar, Nimbus, Prysm, Teku, Grandine) and six execution clients (Besu, Geth, Erigon, Nethermind, Reth, Nimbus-EL) have Docker images available for Platåberget testing.
Since the Merge in September 2022, Ethereum has operated with an informal separation between block proposers (validators) and block builders (entities that assemble transaction payloads). This separation is currently handled off-chain through MEV-Boost, a system of trusted relays. Approximately 88% of Ethereum blocks flow through MEV-Boost today.
EIP-7732 moves this separation into the protocol itself. The key mechanical changes:
The data propagation window expands from approximately 2 seconds to roughly 9 seconds. This wider window is not a latency increase for users; it restructures how the 12-second slot is divided between proposing and building, giving builders more time to assemble payloads and the network more time to propagate larger blocks.
MEV implications: ePBS does not eliminate maximal extractable value. The economic incentive for sandwich attacks, frontrunning, and backrunning persists. What changes is the competition surface. Builder competition moves on-chain, making bid amounts, commitments, and payments transparent and auditable. The relay market — currently dominated by Ultra Sound (32.3%), Titan (24.75%), bloXroute (~26%), and Flashbots (3.44%), according to late 2025 data — becomes optional infrastructure rather than a trust-critical bottleneck.
For home stakers running solo validators, ePBS is a meaningful change. Smaller validators can participate in block production without relying on a relay operator's uptime, reputation, or geographic proximity. The protocol handles the builder handoff directly.
Block-Level Access Lists (BALs) introduce a per-block manifest that maps every account address and storage slot the block touches, along with post-execution state values. Historical data from Ethereum researchers shows average BAL size of approximately 70 KiB per block.
The core benefit: parallelization. By declaring state access in advance, nodes can identify which transactions touch disjoint storage slots and execute them simultaneously. According to Ethereum researcher Toni Wahrstätter, 60-80% of transactions access disjoint storage slots, enabling effective parallel processing.
BALs unlock four specific capabilities:
This is the prerequisite for Ethereum's gas limit roadmap. The 200 million gas target — a 3.33x increase from the current 60 million — becomes feasible only when nodes can process blocks fast enough to avoid propagation delays. BALs, combined with ePBS's wider propagation window, provide the technical foundation.
The gas limit itself is not hardcoded by Glamsterdam. Validators set it through the existing gas-vote signaling mechanism. The expectation is a gradual step-up as node operators verify their hardware handles larger blocks without degradation.
Glamsterdam ships ten EIPs under Meta EIP-7773:
| EIP | Description | |---|---| | EIP-7732 | Enshrined Proposer-Builder Separation | | EIP-7928 | Block-Level Access Lists | | EIP-7708 | ETH transfers emit logs (ERC-20 Transfer event format) | | EIP-7778 | Block gas accounting without refunds | | EIP-7843 | SLOTNUM opcode | | EIP-7954 | Contract size increase (24 KiB → 64 KiB; initcode 48 KiB → 128 KiB) | | EIP-7976 | Calldata floor cost increase | | EIP-8024 | Backward-compatible SWAPN, DUPN, EXCHANGE opcodes | | EIP-8037 | State-creation gas cost increase | | EIP-8159 | eth/71 Block Access List Exchange protocol |
Additionally, EIP-2780 (resource-based intrinsic transaction gas) is listed as "Considered for Inclusion" but not yet finalized.
Three EIPs collectively reprices gas to reflect actual resource consumption:
EIP-8037 (State creation costs): Introduces a fixed cost per state byte (CPSB) for operations that expand Ethereum's permanent database. Creating new accounts now incurs additional "state gas" calculated as STATE_BYTES_PER_NEW_ACCOUNT × CPSB, making permanent state growth more expensive.
EIP-7976 (Calldata floor cost): Increases the minimum cost of calldata, discouraging L2s and other heavy calldata users from consuming excessive block space at below-cost rates.
EIP-7778 (No gas refunds): Eliminates gas refunds for storage deletion. The current refund mechanism creates a price asymmetry that incentivizes gas token farming and complicates block gas estimation.
EIP-7708 (ETH transfer logs): A functional change rather than a pricing one — native ETH transfers now emit a log matching the ERC-20 Transfer event format. This eliminates the need for trace-based methods (trace_transaction, debug_traceTransaction) to track ETH movement, reducing infrastructure costs for exchanges, block explorers, and analytics platforms.
If EIP-2780 is ultimately included, it would decompose the legacy 21,000 gas flat fee into resource-specific components: 12,000 for signature recovery and block inclusion (TX_BASE_COST), 3,000 for cold account access (COLD_ACCOUNT_ACCESS), and 6,000 for balance writes (TX_VALUE_COST). Zero-value transactions would drop to 15,000 gas; self-transfers to 12,000.
Glamsterdam's capacity expansion directly benefits Layer 2 rollups. The wider data propagation window (2 seconds → 9 seconds) means Ethereum can carry more blobs per block, expanding the data availability budget that rollups draw from. Since Dencun's EIP-4844 reduced L2 data posting costs by approximately 90% via blob transactions, each subsequent capacity increase compounds the cost advantage.
For rollup operators: larger blocks and higher gas limits mean more room for blob data submission, which over time should stabilize L2 data costs even as rollup activity grows. The BAL mechanism also makes it possible for nodes to verify rollup-submitted data more efficiently through parallel validation.
The contract size increase (EIP-7954) has direct implications for L2 smart contracts. Raising the maximum deployed contract size from 24 KiB to 64 KiB and initcode from 48 KiB to 128 KiB removes a constraint that has forced developers to split complex contracts across multiple deployments, adding gas overhead and code complexity.
Two proposals were excluded from Glamsterdam:
EIP-7782 (6-second slot times): Reducing slot time from 12 seconds to 6 seconds was declined. The change conflicts with ZK proving workflows and was deemed insufficiently tested for inclusion. Shorter slots would have doubled Ethereum's theoretical throughput but at a cost to decentralization — home stakers with slower hardware would face higher miss rates.
FOCIL (Fork-Choice Inclusion Lists, EIP-7805): A censorship-resistance mechanism where 16 randomly selected attesters nominate transactions that must be included in blocks. FOCIL was moved to the subsequent Hegotá upgrade (targeted H1 2027) to avoid interaction complexity with ePBS. The two systems operate on overlapping parts of the block production pipeline, and core developers determined that shipping both simultaneously introduced untested risks.
Validators and node operators must update both consensus and execution layer clients before the mainnet activation date. The Prysm client bug during Fusaka — which cost validators approximately 382 ETH in lost rewards across 248 missed blocks over 42 epochs — serves as a reminder that client updates carry execution risk.
Wallet developers and indexers face a breaking change: any tool that relies on a hardcapped maximum gas limit will break post-Glamsterdam and requires updating. Gas estimators, transaction simulators, and fee prediction models all need recalibration.
Application developers should migrate ETH transfer tracking from trace-based methods to eth_getLogs to take advantage of EIP-7708's native transfer logs. Testing gas assumptions on Platåberget is advised before mainnet activation.
ETH holders have no required action. There is no token migration, no chain split risk, and no user-initiated upgrade step.
Glamsterdam is an infrastructure-layer upgrade. It does not introduce new token standards, yield mechanisms, or user-facing applications. What it does is restructure the economic and computational pipeline through which every Ethereum transaction flows — from how blocks are built and proposed, to how transactions are executed and priced.
The practical significance is in what it enables rather than what it delivers directly. A 200 million gas limit is not a Glamsterdam feature; it is a Glamsterdam consequence. Parallel execution is not a marketing claim; it depends on 60-80% of transactions accessing disjoint state, a figure that could shift as usage patterns change. ePBS does not eliminate MEV; it makes the competition transparent.
For the Ethereum ecosystem, the upgrade represents a bet on scaling the base layer rather than deferring all throughput gains to Layer 2. Whether validators gradually vote the gas limit toward 200 million — and whether node hardware across the network handles the load — remains an open question that Platåberget, Sepolia, and Hoodi testing is designed to answer.
The next upgrade, Hegotá, is targeted for H1 2027 and is expected to include FOCIL for censorship resistance.