Stellaris Patch Notes: Latest Update (Oct 6, 2026)

The latest Stellaris update is “Stellaris 4.5.2 released [checksum 9776]”, shared on Steam on October 6, 2026. You can find version 4.5.2 ‘Cygnus’ on Steam, GOG, and the Microsoft Store. Nomadic Knights of the Toxic God can now use Arkships to detoxify toxic terraforming candidates. They’ve split and renamed weapon and defense preference policies. Plus, balance changes affect armor upkeep, Fire Cult, Pilot Project, and Covenant bonuses, along with a long list of bug fixes.

What changed in 4.5.2

New content and improvements

• Nomadic Knights of the Toxic God who tame or slay the Toxic God can Detoxify Toxic Terraforming Candidates with Arkships.
• Defense platforms get their own weapon and defense preference policies. The starbase strike craft weapon preference policy is removed.
• Nomadic empires gain the Weapon Preferences (Arkships) and Defense Preferences (Waystations) policies.
• Starting Fleet Doctrine, Weapon Preferences and Defense Preferences policies are now randomized, weighted towards the empire's default preferences.
• Fire Cult combination jobs appear for any empire that meets the same conditions as the base job.
• Logistic Ships now show Waystations in the Megastructure Build Menu alongside their Build Waystation Button.

Balance changes

• Conserve approach for Operational Reserves now gives -50% Specialist Job Efficiency instead of -50% output for Bureaucrats and Researchers.
• Armor now costs the same energy and alloy upkeep as a shield of the same tier, down from double.
• Maulers are now slightly slower.
• Pilot Project bonuses now apply only to Cyborg Pops, giving +15% to Elites, +7.5% to Specialists, +10% to Workers and +5% to all.
• Fire Cult now grants Job Efficiency to Fire Dancers instead of Unity output, scaling with each Pop Group's Habitability.
• Experiment Engineers produce 1 of each research type instead of 2, with upkeep halved.
• Telepaths under the Covenant with the Whisperers in the Void give 1 of each Research per rank, down from 1.5.
• Franchising Civic can now ignore Opinion, Trust and Embassy requirements for proposing Subjugation.

Bug fixes

• Choosing an ethic for your uplifted species now applies that ethic to their pops.
• Fleets no longer stay locked in a battle forever when one of their ships drifts out of weapon range.
• Fixed Imperious Architecture not working.
• Fixed starbase weapon and defense policies not working if the ship auto-designer is turned off.
• A colony that revolts with another empire's backing now joins that empire instead of becoming independent.
• Making peace in one war no longer ends occupations that belong to a second war against the same empire.
• Nomadic Knights of the Toxic God can settle at the Toxic God system and no longer get stuck after losing the Order's Keep Arkship.
• Covenant telepath bonuses now apply as soon as the Covenant is formed, instead of one year later.

UI and AI

• Weapon and defense preference policies are renamed with their targets in parentheses so they appear together.
• The Military Policies window is taller and wider, and policy windows sort alphabetically.
• The Shroud tab no longer opens itself after you breach the Shroud or start as a Shroudwalker Apprentice.
• Logistic Ships dropoff automation now checks stockpile fullness monthly.
• The AI now values the Aquatic trait on species that use the Wet Climate Mods planet preference.

Stability and modding

• Fixed a crash when loading a save with an unrecognized asteroid belt type.
• Fixed a crash on startup caused by a missing or empty language list.
• Reduced late game micro freezes with nomad AIs.
• Added the DESIGNER_STARBASE_WEAPON_PREF_MUL define and the is_preferred_platform_weapons trigger.
• Added set and clear effects for AI platform weapon preference, armor ratio and shields ratio.
• Added define STATION_BUILD_DISTANCE_MAX for how far the AI and fleet automation look for civilian fleet tasks.

Read the full official patch notes on Steam.

Recent Stellaris updates

Date	Update	What it does	Source
Oct 6, 2026	Stellaris 4.5.2 released [checksum 9776]	Stellaris 4.5.2 'Cygnus' is a hotfix that adds Arkship detoxifying, reworks weapon and defense policies, rebalances several civics, and fixes many bugs.	Official notes
Oct 1, 2026	Stellaris Dev Diary #434 – 4.5.2 'Cygnus' Tentative Patch Notes	Stellaris 4.5.2 'Cygnus' adds a Toxic God detox ability, new nomad weapon and defense policies, many balance tweaks and a long list of bug fixes.	Official notes
Sep 24, 2026	Stellaris 4.5.1 released (checksum 358e)	Hotfix 4.5.1 'Cygnus' fixes a common multiplayer Out of Sync, many crashes, and adjusts fleet automation and a nomad Synaptic Lathe rule.	Official notes
Sep 22, 2026	Stellaris 4.5 "Cygnus" now available!	Stellaris 4.5 "Cygnus" is a free Custodian update with over 350 bug fixes, a Pop Group rework, Faction changes and native Apple Silicon support.	Official notes
Sep 17, 2026	Stellaris Dev Diary #433 – 4.5 'Cygnus' Preliminary Release Notes	Preliminary 4.5.0 'Cygnus' notes cover reworked pop ethics and factions, new auto-designer policies, many balance changes and a record number of bug fixes.	Official notes
Sep 10, 2026	Stellaris Dev Diary #432 – Yet More About 4.5 'Cygnus'	Open Beta Update #9 adds many fixes and balance tweaks, and previews AI economy changes that are still in review.	Official notes
Sep 3, 2026	Stellaris Dev Diary #431 – 4.5 'Cygnus' Development Continues to Continue		Official notes
Aug 27, 2026	Stellaris Dev Diary #430 – 4.5 ‘Cygnus’ Development Continues		Official notes
Aug 13, 2026	Stellaris 4.5 'Cygnus' Open Beta Update 5 (bc43)		Official notes
Jul 15, 2026	Stellaris 4.5 'Cygnus' Open Beta Update 4 (e6fd)		Official notes
Jul 10, 2026	Stellaris 4.5 'Cygnus' Open Beta Update 3 (aa56)		Official notes
Jul 9, 2026	Stellaris 4.4.6 hotfix released (fdde)		Official notes

How often does Stellaris get updated?

Stellaris has had 10 patch announcements on Steam in the last 90 days and 24 in the past year, roughly one every 6 days.

Stellaris patch notes FAQ

When was the last Stellaris update?

The most recent Stellaris update is "Stellaris 4.5.2 released [checksum 9776]", posted on Steam on Oct 6, 2026.

What changed in the latest Stellaris patch?

Version 4.5.2 'Cygnus' is available on Steam, GOG and Microsoft store. Nomadic Knights of the Toxic God can use Arkships to Detoxify Toxic Terraforming Candidates. Weapon and defense preference policies are split and renamed. Balance changes touch Armor upkeep, Fire Cult, Pilot Project and Covenant bonuses, alongside a long list of bug fixes.

How often does Stellaris get patched?

Stellaris has had 10 patch announcements on Steam in the last 90 days and 24 in the past year, roughly one every 6 days.

Where can I read the official Stellaris patch notes?

The developer posts full patch notes on the game's Steam news page. We link each one in the table above.

More on Stellaris

• Stellaris stats, news and reviews
• Is Stellaris cross platform?
• Stellaris news on Steam

How we write these: Explosion summarizes the developer’s official Steam announcements and links the original notes. This page checks for new patches several times a day.