Subnautica 2 Guide: How to Increase Inventory Size

Subnautica 2 drops you into the waters of Zezura with just 20 inventory slots and 5 hotbar spaces. You will fill those up within minutes of your first dive. The game does not spell out how to fix this, and most players spend way too long juggling storage chests before realizing there is a permanent upgrade system hidden inside the abandoned colony outposts scattered across the map. Here is exactly how it works and where to find it.

How does the inventory upgrade system work in Subnautica 2?

The upgrade system is tied to Biobeds found inside colony outposts throughout Zezura. These are the same beds used to reset your spawn point, so they are easy to walk past without a second look. What most players miss is the computer terminal attached to each Biobed. Interacting with that terminal for the first time gives you a permanent upgrade, and the game confirms it with the message: "Endurance adapted. Inventory expanded."

There are two types of upgrades available through this system:

• Endurance upgrades add 3 inventory slots each time you claim one.
• Dexterity upgrades expand your hotbar space.

Neither upgrade is repeatable at the same terminal. Each Biobed terminal gives its bonus once, so finding multiple outposts is the only way to keep growing your carrying capacity.

How to find Biobeds

Zezura is large enough that stumbling onto outposts by accident will take hours. The faster method is working with NOA, your AI companion. NOA sends you coordinates for colonist black boxes, but only after you spend time scanning items in the world. The more you scan, the more coordinates NOA provides, and those coordinates lead directly to outposts with Biobeds.

Subnautica 2 Guide: How to Increase Inventory Size (Image from Eurogamer)

For a deeper look at how the map is structured and why distances between outposts vary so much, the Subnautica 2 early access map size guide breaks down what Unknown Worlds has confirmed about the world's depth and scale.

Known Biobed locations and upgrade types

Here are confirmed early-game Biobed locations relative to the Lifepod:

These are early-access locations and may shift as Unknown Worlds updates the game. Cross-reference these distances against your in-game compass when navigating.

What is the fastest way to increase inventory slots early?

Priority order for early inventory expansion:

1. Scan everything you encounter from the moment you start. This feeds NOA's black box system and gets you coordinates faster.
2. Head to Chap's base first (220 meters southeast, 40 meters deep). It is the closest confirmed Endurance upgrade to the Lifepod.
3. Follow NOA's coordinates as they arrive rather than exploring randomly.
4. Pick up the Portable Locker found in the cave directly beneath the Lifepod. This chest appears to respawn periodically, so you can potentially collect more than one. Use it to ferry bulk materials back to your base instead of clogging your personal slots.

Carrying light also helps more than players expect. A spare battery, one snack, and one drink covers most dive scenarios. Everything else can wait in a Portable Locker or a base storage chest.

Are there other ways to manage carrying capacity?

Beyond Biobed upgrades, two additional options exist based on available information:

• Portable Lockers let you cache materials mid-dive and carry them back to base in bulk rather than making multiple trips.
• The Tadpole vehicle reportedly has a haulage module that allows stowing items inside the sub. This module had not been fully tested at the time of writing, so full details on its capacity are not yet confirmed.

For players still getting their footing on Zezura, the Subnautica 2 beginner's guide covers oxygen management, base building, and navigation alongside inventory tips to help you survive the early hours.

For the full picture on everything confirmed for the game so far, the Subnautica 2 guides hub has everything you need to stay ahead as the game expands.