Project Zomboid Build 42.20 moves to stable on July 29

Project Zomboid Build 42.20 will move directly to the stable public branch on July 29, 2026. The Indie Stone listed the current stable build as 41.78.19 and the IWBUMS beta as 42.19.0, then set 42.20 as the next public stable handoff. For players, the main issue is save compatibility.

Build 41 save games will not work with Build 42. Players who want to stay on Build 41, including server owners and multiplayer groups, need to use Steam's “Game Versions & Betas” menu and select the “legacy41” beta branch before the update. Unstable 42.19 saves will also be incompatible with 42.20, so those players need the separate “42.19” branch to finish existing runs.

The 42.20 update targets character spawns, controllers, meat yield from butcher hooks, vehicle towing, and multiplayer zombie culling. After the stable move and any required hotfixes, The Indie Stone plans a feedback-driven patch focused mainly on late-game adjustments, then releases for WorldZed, TileZed, AnimZed, an expanded modding guide, and more modding support.

The studio also says the rest of 2026 will include a Build 42 Support Update covering optimization, additional modding support, controller and multiplayer improvements, and player-requested polish that missed the stable cutoff. The r/pcgaming post shared the date and branch instructions; comment access was limited through RSS, so the concrete community signal here is the server-and-save warning ahead of July 29. Source: The Indie Stone.