The price of Subnautica on Steam will increase from 19.99 US dollars to $24.99 on September 29, 2017. This price increase does not apply to Xbox One Game Preview.
On Steam, we are confident we have brought Subnautica to level of quality that justifies a launch price increase. On Xbox, we have a great deal more work to do and it would be inappropriate for us to increase the price at this time.
We can’t give any dates or predictions for launch of Subnautica on Xbox One. There is a great deal of performance work for us to complete before we can do so, and we cannot predict how long that work will take. Rest assured we agree that frame-rates are not acceptable, and we will increase them.