Can you say Costco's in a sentence or is it Costco?

Answer:
If you are talking in plural terms, you can say Costcos.
Ex: there are 3 Costcos within a 10 mile radius of my house.

If you are talking in ownership terms, you can say Costco's.
Ex: Costco's price for DVDs are much better than Joe's DVD Shop.
First answer by Akiwimumof3. Last edit by Akiwimumof3. Contributor trust: 14 [recommend contributor recommended]. Question popularity: 3 [recommend question].