Version history

Fifteen years of Project Zomboid in one place: from a paid tech demo in 2011 to Build 42.21, with every major build, what it added and when. Newest first; filter by era. Updated for Build 42.21, November 2026.

An overgrown lot — Fifteen years in development

01Era

Every major release

Date	Build	What it added
27 Oct 2026	42.22 pre-release	“Moving on Up”: ladders and crowbar break-ins reported; the Unstable branch retired in favour of pre-releases
28 Sep 2026	42.21 Stable	“Re-population of the Dead”: zombie duplication fixes, XXL tree fixes
26 Aug 2026	42.20.4	Security hotfix on all branches (with 42.19.2 and 41.78.21 Legacy)
17 Aug 2026	42.20.3	Servers handle up to 254 players; loading hang fixes
5 Aug 2026	42.20.1 and 42.20.2	Multiplayer and memory fixes
29 Jul 2026	Build 42 Stable (42.20.0)	Build 42 becomes the default: a map about twice the size, basements, animals, crafting, server-authoritative multiplayer. Price rises to $24.99
2 Jun 2026	42.19	Controller remapping; the last Unstable before Stable
11 May 2026	42.18	Modding fixes and multiplayer polish
22 Apr 2026	42.17	Start anywhere in Knox Country; VHS for nine skills
31 Mar 2026	42.16	Occupations and traits reworked; Tinkerer and Target Shooter; older saves incompatible
9 Mar 2026	42.15	Apocalypse, Outbreak, Rising and Extinction modes; six new guns; gamepad aiming; jamming on in Apocalypse
17 Feb 2026	42.14	Ammunition rework: .223 removed, revolver to .357
11 Dec 2025	42.13	Build 42 multiplayer on Unstable
Mar 2025	42.5	Raccoons and new firearms content (reported)
17 Dec 2024	Build 42 Unstable (42.0)	Crafting rebuilt; animals; basements; new lighting; a bigger map
8 Dec 2022	41.78.16	Final Build 41 hotfix before work moved to 42
10 Nov 2022	41.78	The last Build 41 feature update
20 Dec 2021	Build 41 Stable	Build 41 with multiplayer becomes the default
16 Dec 2021	Build 41 multiplayer beta	The new multiplayer opens for public testing
16 Oct 2019	Build 41 IWBUMS	Animation and character overhaul; new combat; visible clothing; injuries; Louisville
30 Oct 2018	Build 40: weather	Temperature; storms, fog and seasons; the C++ zombie population manager
May 2018	Build 39: vehicles	Drivable vehicles with physics, parts and breakdowns; Mechanic; hotwiring
Sep 2017	Build 38	Riverside and the Knox Heights Country Club; graves
Apr 2017	Build 37	Lootable maps; map notes and symbols
Jan 2017	Build 36	Player trading; furniture pickup
Dec 2016	Build 35	Rosewood, March Ridge and the prison; voice chat; metalwork; factions and safehouses
2016	Build 34	Food revamp; freezers; nutrition; new lighting and line of sight
Jan 2016	Build 33	FMOD sound; radio and TV broadcasts; walkie-talkies; herbalism; movable furniture
Aug 2015	Build 32.20	Steam Workshop; Steam servers; new crafting UI
Jun 2015	Build 32	Zombie respawn and migration; generators; Electrician and Engineer; explosives
Mar 2015	Build 31	Professions and traits rewritten; keys and locks
Dec 2014	Build 30	New health and injury system; erosion and seasons; Kentucky weather; split-screen co-op
Oct 2014	Build 29	Ambient sound; foraging; survivalist recipes
Sep 2014	Build 28	Semi-3D sound; ranged weapon overhaul; weapon mods
Summer 2014	Build 27	Public multiplayer server list; trapping; the West Point mall; 3D player and zombie models
Spring 2014	Build 26	Fishing; new cooking system
Feb 2014	Build 25	Multiplayer testing; custom maps; thunder and lightning; weapon repair
8 Nov 2013	Steam Early Access	Launch on Steam; West Point; new items and recipes; lighting options
11 Sep 2012	Steam Greenlight	In Valve’s first batch of ten Greenlit games
15–16 Oct 2011	The burglary	Two laptops stolen from the developers’ flat with months of unbacked-up code
19 Sep 2011	Desura Alphafunding	One of the first five Alphafunding games on Desura
28 May 2011	Paid alpha tech demo	First public sale; a leak forced a free public demo the next day

Dates for Builds 25 to 38 are the months The Indie Stone gives; exact days vary between sources. Full notes for 42.20 onward are on patch notes.

02Era

Four eras

2011 to 2013: the indie years

A two-person studio, a paid alpha, a stolen laptop, Desura and Greenlight. Project Zomboid nearly did not survive its own development.

2013 to 2018: Early Access

Steam launch, then a build every few months: multiplayer, Rosewood and Riverside, radio and TV, factions, vehicles in Build 39 and weather in Build 40.

2019 to 2022: Build 41

The animation overhaul that made the game feel modern, Louisville, and in December 2021 the multiplayer that brought a wave of new players.

2024 to now: Build 42

Crafting rebuilt, animals, basements and a map twice the size, eighteen months on Unstable, and Stable on 29 July 2026. See Build 42: everything new.

03Era

Price history

When	Price	Why
2011	Alpha pre-order	Paid tech demo
Nov 2013	£10 (from £5)	Steam Early Access launch
2022	$14.99 → $19.99	After Build 41 and multiplayer
29 Jul 2026	$19.99 → $24.99 (£16.75 → £22.49)	Build 42 Stable

Project Zomboid has no Steam achievements. Mods add them.

04Era

Branches you can still play

Stable (default)

Build 42.21. What you get when you install.

legacy41

Build 41.78.21 for saves and servers not ready to move. Steam: Properties, Betas.

Pre-release

From 42.22 The Indie Stone tests updates as short pre-releases instead of a long Unstable branch.

How to switch, and what happens to saves and mods, is in Build 42: everything new.

05Era

Quick answers

When did Project Zomboid come out?

A paid alpha in May 2011; Steam Early Access on 8 November 2013. It is still in Early Access.

When did Build 42 go Stable?

29 July 2026, as version 42.20.0.

What is the latest version of Project Zomboid?

Build 42.21 Stable (28 September 2026), with 42.22 in pre-release from 27 October 2026.

Does Project Zomboid have achievements?

No, not on Steam. Mods add them.

Can I still play Build 41?

Yes, on the legacy41 branch in Steam’s Betas tab.

Compiled from The Indie Stone’s own version history and blog, Steam news for app 108600, GOG build records, Wikipedia and press reports. Build 42 Unstable dates from GOG and Steam can differ by a day. Items marked reported were not checked against the full patch notes.