Subnautica OST

The Subnautica soundtracks were composed by Simon Chylinski. Around January 18, 2018, the official album was gifted to all buyers of the game version on Steam. It can be found and listened to in the Steam Library.

If the soundtracks is not in your Steam library, you can follow these steps to get the soundtrack if you are playing Subnautica on Steam.

Go to your steam library and right-click on the game. There should be a button that says "Properties" . Click it.
Next, click on "Local files" , browse in the local files and then click on "OST". From here, create a shortcut or copy the file to music.
Sit back, and enjoy the Subnautica's soundtracks. :)

It is also available from several different websites;

List of Tracks

#	Title	Played when
1	Salutations	Main Menu
2	Into The Unknown	Safe Shallows
3	Tropical Eden	Floating Island and Safe Shallows
4	God Rays	Safe Shallows and the during Dangerous Creatures Update trailer
5	In Bloom	Kelp Forest
6	Precipice	-
7	Sun & Moon	Kelp Forest
8	Finding Life	Safe Shallows
9	Crush Depth	Jellyshroom Cave
10	What are You	Primary Containment Facility
11	Original Inhabitants	Alien Caches
12	A Tendency to Float	-
13	Abandon Ship	End credits, fire in Cyclops
14	Ahead Slow	-
15	Alien Expanse	Entering the Quarantine Enforcement Platform or Sparse Reef biome
16	Alien Passageways	Gravity Lift in the QEP
17	Alien Spaces	Power room in the QEP
18	Alterra Science	During the Alterra Science Update trailer
19	Amid the Kelp	Kelp Forest
20	Ancient Aliens	Alien Caches
21	Arc Lights	When in the Seamoth or Prawn Suit
22	Blood Crawlers	Blood Kelp Zone
23	Blueprint	Aurora Prawn Bay
24	Bone Fields	Bone Fields
25	Bring a Medpack	Blood Kelp Zone and the Aurora
26	Buoyancy	Kelp Forest, Grassy Plateaus
27	Caverns	In Safe Shallows Caves
28	Coral Reef	Safe Shallows
29	Crash Site	Crash Zone
30	Cuddlefish	During the Cuddlefish Update Trailer
31	Dark Matter Reactor	When the player is in the Aurora
32	Exosuit	When the player is in a Prawn suit and During the PRAWN Update trailer
33	Fear the Reapers	Blood Kelp Zone
34	First Immersion	Grassy Plateaus
35	Ghost Tree	Tree Cove
36	Ghosts	During the Bones Update Trailer
37	Habitat	When the player is in a Seabase, the Grassy Plateaus and during the Machinery Update trailer
38	Infected	When the player enters the Disease Research Facility & The Infected Update trailer
39	Islands Beneath the Sea	In Grassy Plateaus, Sea Treader's Path, Sparse Reef, and Underwater Islands.
40	Lava Castle	When the player is in the Lava Castle, Alien Thermal Plant or the Blood Kelp Zone
41	Leviathan	During the Voice of the Deep Trailer
42	Cycle of Life	When the Drive Core is repaired, when the Sea Emporer dies and when the player is cured.
43	Lost River	When the player enters the Lost River or Grand Reef biomes
44	Maneuvers	Grassy Plateaus and during the Power Nap Update trailer
45	Mushroom Forest	When the player is in a Mushroom Forest biome
46	Observatory Zen	When the player is in an Observatory
47	Red Alert	When the Cyclops is under attack by Leviathan class predators & The Silent Running Trailer
48	Rock It!	During the Ghost Update Trailer
49	Safe in Kelp forest	When the player is in the Kelp Forests
50	Seamoth	Intro cutscene; When a fire is onboard the Cyclops
51	Shadow of the Reefback	When the player is in the Grassy Plateaus
52	Shallows	When the player is in the Safe Shallows
53	Sunbeam	When the Sunbeam countdown starts, Safe Shallows
54	Unknown Flora	Upon arrival at the Underwater Islands
55	Violet Beau	Upon arrival on the Mountain Island
56	Lift Off	Launch of the Neptune Escape Rocket

Trivia

Track 32, is named "Exosuit" because the original name for the Prawn Suit was Exosuit, and the track had been made prior to the name change.
Rock It! was originally called Void and Cuddlefish was originally called Dive Buddy.
In Alien Expanse, Donald Trump saying "China" can be heard.

One track called Docking was used in the Coffee and Castles trailer but is not on OST or in the game.
- Docking was first used in Natural Selection II