All Warhammer 40k Codex release dates in 2025

30 armies have now received their 10th edition Warhammer 40k codex (or at least an index update) - with another just about to drop, and more certain to come later. We're keeping this guide stocked with all the 10th edition codex release dates we know are coming in 2025 and beyond, and the latest new releases too. There's also handy info on how to use your codexes, and links to our army guides.

If you're new to Games Workshop's premier sci-fi miniature wargame, our expert guide to the Warhammer 40k factions will help you get oriented in this huge sci-fi world - there's more than just Space Marine chapters.

For now, though, let's run through the latest official codex rulebooks - some already released, some scheduled, and others as yet mired in mystery. You can click the links below to find the info you need:

• Confirmed 10th edition codex release dates
• Chaos Daemons rules update
• All free Grotmas Calendar detachment PDFs
• How do I redeem Warhammer 40k codex codes?
• What are Warhammer 40k codexes?

Confirmed 10th edition codex release dates

The latest Warhammer 40k Codex is Codex: Drukhari, which went up for pre-order on September 27 and released on October 11.

Of the at least 27 10th edition codexes we expected to arrive over the (roughly) three years of the edition, a whopping 30 factions now have either a codex or an updated index, with three more to go. This includes a re-release of Index Deathwatch - which was briefly deprecated by Codex Imperial Agents - and mid-edition refreshes of both Index Chaos Daemons and Index Imperial Knights.

Here's a table showing all the codexes (and updates) released so far:

If you're wondering when a particular codex released during 9th edition 40k, check out our guide to 9th edition codexes.

Here's our run-down of the upcoming codexes we're still expecting and their release date, or estimated release window:

The Drukhari marks the last confirmed codex, but we're still expecting to see a second one for the good old Space Marines. That's because one of GW's 2024 release 'roadmaps' included the above silhouette of a Primaris Space Marine Reiver, marked as coming in "the future". This almost certainly means that, as in 8th Edition (2017-2020) the beloved Adeptus Astartes will be getting a second 10th Edition 'dex before the edition draws to a close in Summer 2026.

We had been hoping for a little more, though. At the end of March, Games Workshop included images of Salamanders and Imperial Fists Space Marines on its Codex roadmap, suggesting that standalone Codex supplements are coming for these first-founding chapters. Since then the firm has revealed new character models for both chapters, plus minis for new Raven Guard, Iron Hands, and White Scars characters. They've all received standalone free detachment rules, too - which is great, but dashes our hopes of codex supplements.

The surprise release of Codex Imperial Agents in 2024, which collected the rules for Inquisitors, Rogue Traders, Imperial Assassins, and the Deathwatch, seems to bode well for further new (or resurrected) factions to be added to the tabletop game - we'll keep praying to the Emperor of Mankind.

With less than a year left until we're expecting Warhammer 40k 11th edition to drop, though, it seems unlikely GW will give us such a large surprise gift before the sun sets on tenth edition.

Chaos Daemons Rules Update

Games Workshop released a free, updated Chaos Daemons 10th edition index on March 12, 2025 - you can download the free PDF Index here. Though it dashes fans' hopes for a standalone codex this edition, we're encouraged by the decision - the more free rules in the game, the better.

There are a raft of small changes in the rules, with GW highlighting a few themed buffs for the different gods:

• "Bloodthirsters, Skarbrand and Bloodcrushers all get a 3+ Armour Save"
• "Daemonettes and Tranceweavers now have Fights First all the time"
• "Great Unclean Ones now increase the Toughness of nearby Nurgle units"

On the whole, it means that Chaos Daemons remain a fully supported standalone army - but not likely a mainstream choice. Your Plaguebearers, Nurglings, Bloodletters, Horrors, Flamers, and other gribbly nasties are more likely to see play as allies to their favorite Chaos Space Marines, using their rules in the Emperor's Children codex and the similar sections we expect in the upcoming Death Guard, World Eaters, and Thousand Sons 'dexes.

This arrangement, with daemons and mortal followers of a specific god in one army list, is similar to how chaos forces are organised in Warhammer Age of Sigmar armies - and Age of Sigmar does not have a standalone battletome for Chaos Daemons as a whole.

All free Grotmas detachment PDFs

In December 2024, Games Workshop released one new, free, one-off expansion PDF for each army as part of its 'Grotmas Calendar' promotion.

Each PDF adds a full Warhammer 40k detachment, complete with detachment rule, four Enhancements, and six Stratagems, to offer a new way to play each faction. These detachments are available to use in games alongside the ones provided in your faction's codex (or Index, if you don't have one yet).

You can download the detachment PDFs below:

• Death Guard - Flyblown Host
• Dark Angels - Lion's Blade Task Force
• Tyranids - Warrior Bioform Onslaught
• Thousand Sons - Hexwarp Thrallband
• Adeptus Mechanicus - Haloscreed Battle Clade
• Necrons - Starshatter Arsenal
• Adeptus Custodes - Solar Spearhead
• Chaos Knights - Iconoclast Fiefdom
• Imperial Knights - Questor Forgepact
• Grey Knights - Warpbane Task Force
• World Eaters - Vessels of Wrath
• Black Templars - Wrathful Procession
• T'au Empire - Auxiliary Cadre
• Blood Angels - Angelic Inheritors
• Adepta Sororitas - Champions of Faith
• Space Wolves - Champions of Fenris
• Genestealer Cults - Final Day
• Leagues of Votann - Hearthband
• Chaos Daemons - Plague Legion
• Chaos Daemons - Scintillating Legion
• Chaos Daemons - Blood Legion
• Chaos Daemons - Legion of Excess
• Astra Militarum - Bridgehead Strike
• Orks - Taktikal Brigade
• Drukhari - Reaper's Wager
• Aeldari - Armored Warhost
• Chaos Space Marines - Creations of Bile
• Space Marines - Librarius Conclave
• Imperial Agents - Veiled Blade Elimination Force
• Deathwatch - updated Index

How do I redeem Warhammer 40k codex codes?

You'll find a unique Warhammer 40k codex code in the back of each printed Codex. You can register this code on your MyWarhammer account, which will in turn unlock all the datasheets and Detachments from the Codex in the Warhammer 40k app.

You can then use that data in the Battle Forge army builder. You will be limited to just one army list at a time in the app, unless you also have a Warhammer+ subscription.

What are Warhammer 40k codex books?

Codexes are the traditional home for the rules for each Warhammer 40k faction, though Warhammer 40k 10th edition launched with a full set of free 'Index' rules for each army.

As Codexes are released, they supercede the Index, updating rules and points, and adding new Warhammer 40k detachments that give you alternative ways to build your army that will reward you with new abilities, enhancements, and 40k Stratagems.

We also have a rundown of the best Warhammer 40k starter set for your needs, too. You'll find lots more at our Warhammer 40k homepage.