Let the baked pie cool completely and then place in the freezer, uncovered. When completely frozen, tightly wrap the pie in a few layers of plastic wrap. You can also use a large freezer bag. A baked apple pie will stay good in the freezer for up to 4 months. When you are ready to serve, let the pie thaw at room temperature for one hour. Reheat the pie in the oven at 375°F on the lowest oven rack for 35 to 40 minutes or until heated through.