To make the soundtrack more readily available, we've moved the soundtrack from the game itself to additional content. If you already own a copy of Subnautica on Steam, you will automatically be credited with a free copy of the soundtrack to download. You can find and download this directly from the game listing in your Steam Library.
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Additionally, for the next seven days, any purchase of Subnautica on Steam will also come with the soundtrack. After that, it will be available to purchase for $9.99.
Enjoy, and happy diving!
- Unknown Worlds