A block or chunk of Swiss cheese can last one to two months in the refrigerator before it starts to mold, but sliced and cut Swiss cheese will last only one month in the refrigerator before molding. The semihard cheese lasts six to eight months when stored in the freezer.
Storing Swiss cheese at the proper temperature is the key to prolonging it's shelf life. The temperature of the refrigerator should be at 40 degrees Fahrenheit, and the cheese should be wrapped in its original packaging or an air tight container. To prevent the Swiss cheese from going bad, do not keep it out for more than two hours at a time.