Freezing butter is a very good way to take to advantage of sales and to help assure you have fresh quality butter on hand. The fresher the butter is, the greater potential longer-term storage time. While Challenge packages suggest butter may be kept frozen up to 4 months, very fresh butter has been frozen successfully for up to 12 months at 20°- 30°F. Although freezing will prolong shelf life, gradual flavor and texture changes will occur over time even in frozen product. For the best results, freeze fresh butter in its original carton within a plastic freezer bag.