Subnautica 2: how to join the Experimental branch on Steam and Xbox — and the save file trap

Unknown Worlds opened an Experimental branch for Subnautica 2 on August 12, 2026, available on Steam and Xbox. This is a first for the game since it entered early access, and it fits with the open development policy the studio champions.

The appeal is real: this branch offers a preview of the next big update before it lands on the main version — 1.2 in this case. But it comes with a catch that many players will discover too late, and one that can cost an entire save. Here's how to proceed, and what you need to know before clicking.

The catch you need to read first

Let's start here, because this is what matters: saves created on the Experimental branch don't work on the main branch.

The consequence is simple but brutal. If you switch to Experimental, play twenty hours, then decide to go back to the normal version, those twenty hours won't follow you. They're not lost in the strict sense — they remain tied to the branch — but they become inaccessible from the standard game.

The studio also warns that these versions are more likely to contain bugs, including bugs capable of breaking a save. This isn't just a turn of phrase: it's precisely the branch's purpose, which is to catch these issues before they reach everyone.

Hence a common-sense rule: never move your main save over to Experimental. Create a dedicated save there instead, one made to be thrown away.

How to enable the branch on Steam

The process takes a minute:

1. Open your Steam library.
2. Right-click on Subnautica 2, then select Properties.
3. Go to the Betas tab.
4. In the beta participation dropdown menu, select the Experimental branch.

Steam will then download the corresponding version. To switch back, just follow the same steps and select None again.

How to enable it on Xbox

The process goes through a different channel. You need either to own Subnautica 2, or to have an active Game Pass subscription. Sign-up is then done through the Xbox Insider Hub, under Previews > Subnautica 2 Experimental.

Note: as of now, the branch is not available on Epic. Players who own the game there don't have access to it.

What's actually being tested

The branch serves as a showcase for the next major update, 1.2. The studio has drawn a useful distinction in its communication about the game's development pace: some updates are targeted improvements affecting systems or small features, others are emergency fixes, and others still are true expansions that flesh out the world — biomes, creatures, resources, tools, vehicles — and advance the story.

The previous major milestone was 1.1, called Adaptive Measures, released in mid-July. It smoothed out Biomod progression early in the game and added the ability to unlock additional passive slots by scanning creatures with the Bioscanner. This is the thread that 1.2 is expected to continue.

Should you jump in?

The answer honestly depends on what kind of player you are.

• You're playing a long game you're determined to finish. Don't go there. The risk isn't losing the game, it's fragmenting your progress between two incompatible branches.
• You've already cleared most of the current content and you're bored waiting for what's next. That's exactly the target audience: start a fresh save on the Experimental branch, it won't cost your main save anything.
• You want to report bugs. That's the intended use, and it's the only case where suffering through crashes has a useful upside.
• You play co-op. Warning: the whole group needs to be on the same branch. Just one player staying on the main version is enough to block the session.

The precaution to take before switching

Even though saves from both branches are supposed to stay separate, make a manual copy of your save folder before switching versions. That's the basic reflex for any early access game, and it costs thirty seconds. On Steam, this folder is located in the game's local data; just duplicate it elsewhere on your drive.

Second precaution, a more subtle one: note down the version number you were playing on. If you need to roll back, this avoids wondering whether an issue comes from the branch or from an intermediate update to the main version.

What this says about the game's pace

Opening a test branch is a signal in itself. Subnautica 2 entered early access in the spring on PC and Xbox Series, and the studio has since kept up a steady pace of updates. Moving to a model with a test branch means the upcoming additions are big enough to warrant a public validation phase — which is a rather good sign for the content still to come.

For PS5 players, however, nothing changes: Sony's console version still has no release date, and early access remains limited to PC and Xbox Series.

One last note to avoid any confusion over terminology: Subnautica 2 does not yet have a full French client at this stage, and the names of biomes, tools, and creatures you'll come across in the patch notes remain in English. We're therefore keeping the official terms here — Experimental, Biomod, Bioscanner — rather than inventing equivalents that wouldn't match anything on screen.