How Long Can Milk Sit Out Before It Goes Bad?

Place milk at the back of the refrigerator rather than in the door or the front of the refrigerator due to fluctuating temperatures. When stored properly, opened and unopened milk lasts around a week past the "sell by" date. While proper storage helps extend the shelf life of milk, it can still go bad. Typically, spoiled milk has a sour smell, features a lumpy texture and may look discolored.