Ethereum to End Holesky Support in September 2025

Ethereum developers will end support for the Holesky testnet in September 2025. Launched in 2023, Holesky has played a critical role in testing staking mechanisms, infrastructure, and protocol upgrades.

The shutdown of Holesky will affect validators, developers, and infrastructure projects that relied on it for testing. To replace it, the Ethereum Foundation has introduced Hoodi, a new testnet that will serve as the primary platform for testing upgrades. On March 26, Hoodi will activate the Pectra upgrade, ahead of its deployment on the Ethereum mainnet.

Holesky: History and Reasons for Shutdown

Holesky was launched as one of Ethereum’s two main testnets, alongside Sepolia. It was widely used for staking, infrastructure testing, and protocol upgrades, allowing developers to validate new features before deploying them on the Ethereum mainnet.

However, during preparations for the Pectra upgrade, Holesky faced critical technical challenges. Testing triggered major disruptions, requiring weeks of recovery. 

The main issue was an overloaded validator exit queue, preventing validators from actively participating in Pectra testing. With a full validator exit potentially taking up to a year, Holesky was deemed unsuitable for comprehensive testing, leading to its replacement.

The decommissioning of outdated testnets is a standard practice for Ethereum. Previously, Kiln, Ropsten, and Rinkeby were shut down in 2022, followed by Goerli in 2023.

Support for Holesky will officially end on September 30, 2025. In its place, Hoodi will serve as the primary testnet for validators and staking, with support extending until 2028. Meanwhile, Sepolia, which is mainly used for application and tooling development, is set to be phased out in 2026 and replaced by a new testnet.

This gradual infrastructure update allows the Ethereum community to adapt to changes and test future upgrades more effectively.

Hoodi: Ethereum’s New Testnet

Following the announcement of Holesky’s shutdown, Ethereum developers introduced Hoodi, a new testnet set to replace its core functions.

Hoodi is already live and will serve as the primary testing environment for network upgrades, including the upcoming Pectra update. On March 26, Hoodi will activate Pectra, allowing developers to test the changes ahead of their scheduled mainnet deployment in Q2 2025.

Related: What to Expect from Ethereum’s Pectra Update?

Hoodi is specifically designed to support validators and stakers, offering a more stable and efficient environment for testing new solutions. Moreover, its enhanced architecture improves network upgrade testing and enables long-term Ethereum simulations.

Holesky’s New Role: An Experimental Testnet

Despite the end of official support, Holesky will not be fully decommissioned. Instead, developers plan to repurpose it as an experimental network for protocol-level testing.

Holesky will serve as a platform for pushing Ethereum’s technical limits, focusing on:

• Gas limit testing to evaluate its impact on network performance.
• Stress tests to identify potential vulnerabilities before future upgrades.
• Other experimental scenarios critical to Ethereum’s long-term development.

Rather than being completely shut down, Holesky will transition into a research-focused testnet for Ethereum developers. However, Hoodi will take over as the primary testnet, providing a more stable environment for validators and infrastructure providers.