Protocol 24 upgrade guide

This guide is designed to help businesses and developers prepare for Protocol 24, which is a stability upgrade necessary to fix a bug in the state archival feature in Stellar Core. Note that the timeline for the upgrade is much more compressed than normal.

Key dates

• October 20: Stable releases available. Complete!
• October 21 at 2100 UTC: Testnet upgrade. Complete!
• October 22 at 1700 UTC: Mainnet upgrade vote. Complete!

If you run Stellar infrastructure (Stellar Core, Horizon, RPC, Galexie)

Install Protocol 24 releases. If you use Docker images, pull the Protocol 24 builds from the Docker registry. If you build from source or our Debian packages, make sure to also update your stellar-core, stellar-horizon, and stellar-rpc binaries to the Protocol 24 builds.

Please note: When upgrading RPC and Horizon, it may take about one hour to catch up after the upgrade!

If you run a validator

The Protocol 24 upgrade vote is scheduled for October 22, 2025 at 1700 UTC. You should arm your validator with the following command:

upgrades?mode=set&upgradetime=2025-10-22T17:00:00Z&protocolversion=24

If you use a Stellar SDK

No action required. There are no XDR changes in the Protocol 24 upgrade, so you won’t need to update any SDK software.

Below are up-to-date links to all available releases relevant to Protocol 24. In general, please make sure to check release notes for specific instructions and requirements, and unless otherwise indicated, opt for the “Latest Release.”

Stellar infrastructure

• Stellar Core
• Horizon
• RPC
• Galexie

To stay up to date on any and all Protocol 24-related announcements, join the Stellar Developer Discord, where the ecosystem coordinates and shares information about the upgrade.

If validators approve the upgrade, there will be a subsequent vote to enable the state archival feature. Unless you run a validator, no action is required to prepare for that vote.

October 21, 2025: Added note about catch-up time after RPC/Horizon upgrade
October 21, 2025: Updated progress - Testnet upgrade complete.
October 22, 2025: Mainnet upgrade vote, Mainnet upgrade complete.