Seamoth Guide - How to Get, Upgrade, and Use Your Submarine
Updated 2026-08-06 - 12 min read
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Your First Submarine
The Seamoth is a game-changer. It turns you from a slow air-breathing diver into a fast, deep-diving explorer. Getting one is one of the biggest milestones in the game.
This guide covers everything from unlocking to max upgrades.
How to Unlock and Build
To get the Seamoth, you need to:
- Find and scan Seamoth fragments in wrecks
- Build a Mobile Vehicle Bay
- Craft the Seamoth at the bay
Fragments Location
Seamoth fragments are most commonly found in wrecks in the Grassy Plateaus and Mushroom Forest biomes. You need 4 fragments to unlock the full blueprint.
Materials to Build
- Titanium Ingot x1
- Power Cell x1
- Glass x1
- Lubricant x1
- Lead x1
How to Use the Seamoth
Driving the Seamoth is straightforward once you get the hang of it.
- WASD: Move around
- Space: Ascend
- Shift: Descend (or C depending on settings)
- Right click: Exit the vehicle
- Left click: Use active upgrade (if installed)
Important Features
- Built-in oxygen supply (breathe inside)
- Headlights for dark areas
- Storage compartment
- Can take damage from creatures and terrain
Depth Upgrades
The base Seamoth can only go so deep. You need depth modules to go farther down.
| Module | Max Depth |
|---|---|
| Standard | 200m |
| MK1 Depth Module | 500m |
| MK2 Depth Module | 900m |
| MK3 Depth Module | 1300m |
Go below your max depth and the Seamoth takes hull damage. Go too far and it implodes.
All Upgrades
The Seamoth has several upgrade slots for customization.
Essential Upgrades
- Depth Modules (MK1-3): Go deeper. Most important upgrade.
- Seamoth Storage: Extra storage space in the back.
- Solar Charger: Recharges near the surface. Very convenient.
Combat and Utility
- Perimeter Defense System: Shocks nearby creatures. Great for getting away from predators.
- Torpedo System: Fire torpedoes. Gas and vortex types.
- Sonar: Shows terrain and creatures through walls. Great for caves.
Repair and Maintenance
Your Seamoth takes damage from collisions and attacks. Keep it in good shape.
- Repair with a Welder. Carry one in your inventory.
- Park it in a Moonpool. Automatically recharges and can be modified.
- Do not ram things. Collisions cause damage. Go slow in tight spaces.
- Avoid Leviathans. They can one-shot a Seamoth if you are not careful.
Pro Tips
- Always carry a spare power cell. Nothing sucks more than running out of power far from base.
- Use it as a mobile base. You can store supplies and return to it for air while exploring.
- Name your Seamoth. It might sound silly, but it grows on you.
- Park it somewhere safe. Do not leave it where predators can attack it while you are exploring on foot.
- Solar charger is underrated. Near the surface, you basically never run out of power.
Seamoth Guide: SN1 vs SN2 — Same Sub, New Tricks
The Seamoth returns in Subnautica 2 with overhauled modules. If you mastered the SN1 Seamoth, here’s what changed.
| Topic | Subnautica 1 | Subnautica 2 (2026) |
|---|---|---|
| Acquisition | Found fragments in Grassy Plateaus / Kelp Forest | Same biome fragments plus new Aurora wreckage spawns |
| Max depth | 900m with MK3 | 900m (unchanged) but Seatruck now handles 1300m |
| Perimeter Defense | Shocks Stalkers only | Now also reveals hidden Leviathan-class creatures in 50m radius |
| Solar charging | Standard solar cell | Added "Deep Solar" module — charges at 500m (SN2 only) |
| Storage | 4 inventory slots | 6 inventory slots with hotbar quick-swap |
Coming from Subnautica 1? Bookmark this page — the rest of the guide covers SN2-specific mechanics, but this table helps you unlearn old habits.