Short answer
Steam, Epic, Microsoft Store or PC Game Pass, Xbox Series X|S, Xbox Cloud Gaming, and supported handheld Xbox/PC devices are the current platform group to check first for Subnautica 2 crossplay.
The official support page lists Steam, Epic Games Store, and Xbox as official places to get the game. Steam lists Online Co-op and Cross-Platform Multiplayer. The Xbox Store lists PC, Xbox Series X|S, Xbox Cloud Gaming, Handheld, Online co-op, Online multiplayer, Xbox cross-platform multiplayer, Xbox cross-platform co-op, Xbox cloud saves, and Xbox Play Anywhere.
PS5 is not in that current official platform list. Do not buy or wait on a PlayStation copy based on a rumor; wait for an official PlayStation announcement before planning a PS5 co-op group.
Platform matrix
| Platform or version | Current answer | What to check before blaming crossplay |
|---|---|---|
| Steam | Supported PC storefront; Steam lists cross-platform multiplayer. | Make sure every player is on the same current Early Access build. |
| Epic Games Store | Listed by official support as an official distribution platform. | Confirm the live invite flow before treating Epic-specific errors as solved. |
| Microsoft Store / PC Game Pass | Part of the Xbox PC ecosystem listed by Xbox Wire and Xbox Store. | Check Xbox account privacy settings and platform update timing. |
| Xbox Series X|S | Listed by Xbox Store as a supported play platform. | Console online multiplayer may require an active Game Pass subscription. |
| Xbox Cloud Gaming | Listed by Xbox Store as a supported play platform. | Cloud availability can depend on Game Pass tier and region. |
| Xbox/PC handhelds | Xbox Store lists Handheld support, and Xbox Wire names ROG Xbox Ally. | Treat device support separately from network or account errors. |
| PS5 | Not a current official platform in the checked sources. | There is no confirmed PS5 crossplay path to test right now. |
How many players can join?
Plan for up to four players total. Steam describes Subnautica 2 as playable alone or with friends in 4-player co-op, and the Xbox Store lists Online co-op for 2-4 players.
That does not mean every save, invite, or account setting behaves the same across platforms. Co-op is still part of an Early Access game, so keep multiplayer advice tied to the current build.
If crossplay fails
Start with the simple checks before assuming your platform mix is unsupported:
- Confirm everyone is on the current build for their platform.
- If one player is on Xbox, remember that hotfix rollout can lag behind PC while certification clears.
- Check Xbox privacy, family, and online multiplayer permissions for Microsoft accounts.
- Test one direct invite path with only two players before adding the whole group.
- If the error mentions cross-platform play, write down the exact message and platform pair before trying fixes.
This page does not give a universal fix for every invite error. Steam and Reddit threads show that players are running into real connection questions, but the exact fix depends on platform, patch timing, account settings, and the current build.
Buy or install decision
Use Steam if your group is already on Steam and wants the simplest PC path. Use PC Game Pass or Xbox Game Pass if your group is already inside the Xbox ecosystem. Either way, check whether the rest of your group is on a current supported platform before buying.
Do not plan around PS5 yet. The checked official sources do not list PlayStation as a current purchase or download platform.
Version note
Checked on July 17, 2026 against the official Subnautica 2 platform support page, live Steam and Xbox stores, Xbox Wire, and the Hotfix 4 rollout note. Recheck this FAQ after major co-op updates, Xbox certification notes, new storefront launches, or any official PlayStation announcement.