Yes, you can freeze clam chowder. However, we don't recommend freezing it for more than two months as the quality of the soup may suffer over time. To freeze your clam chowder, let it cool completely and then place in quart-sized freezer bags or an airtight container. Be sure to remove as much air as possible before freezing. When you're ready to eat it, let the soup thaw in the fridge overnight and then reheat over low heat on the stovetop.