It depends if it's diet or regular. Diet turns bad after 3-4 months, but regular can be good for a year or more. One interesting story that happened shortly after my husband and I were first married. We had bought a bunch of pop on sale, & had the boxes stacked in the corner of our kitchen. After 9 months, when we got to the case on the bottom, 1/2 of the cans were mysteriously empty (Coca-Cola Classic, in case you were wondering). There was also an odd black film on the floor under the box.