I would say a person who likes spending time at home is called a homebody.

Homebody Opposite: social butterfly

Hey Ibo, You can use "homebody", "hermit" or "recluse". But there's a little difference. A homebody can still have a good time going out with friends, and enjoy other aspects of a normal social life, but prefers to be home. A recluse or a hermit is a person who stays home due to fear of being in public places. Hope it helped:)

Hello Ibo! :) Couch potato, hermit, homebody, introvert(ed), recluse. Antonym: socialite, social butterfly, extrovert(ed). Hope this helps :)

You might use: 'coach potato'. But it is informal and when used it shows disapproval. An antonym could be -I guess- better achieved by using a clause.