Girl Scout cookies can be frozen and enjoyed months after the selling season ends. To best preserve the freshness and quality of Girl Scout cookies, keep them in their original packaging, and freeze them on or before the use by or freeze by date on the box.
When placing Girl Scout cookies in the freezer, it is important to leave space in between each box. If the cookies are still in the original box, Girl Scout cookie lovers are advised to poke a number of small holes in the top and sides of each box to help increase air flow, notes Huffington Post's Jeremy Blachman.
Cookies should be cool or room temperature before they are placed in the freezer. Placing warm cookies in the freezer causes condensation to collect inside the packaging, leading to ice crystals and freezer burn.
Not all types of cookies keep well in the freezer. However, each box of Girl Scout cookies is stamped with a "use or freeze by" date, indicating that all varieties of Girl Scout cookies may be frozen. Some varieties may be eaten while still frozen. Thin mints are a popular cookie to eat as a frozen dessert.