https://www.cnet.com/news/galaxy-s9-plus-trade-in-old-phone-mwc-2018/

Trade-ins will begin on March 2 and it only applies to new Galaxy phones (including the Galaxy S8, S8 Plus and Note 8 too) bought online directly from Samsung.com or through the Shop Samsung App. Depending on what phone you trade-in, in the US you can get up to $350 back. Of course, the money you get back depends on the worth of your old phone, so it's safe to say you'll receive less money the older your phone is and the worse shape it's in.

So what phones are eligible? Check out the list below: