While many soups freeze like a dream, this isn't one of them. Technically you can freeze it - and you should if you're in a pinch and would have to throw it out - but potato soups tend to get a bit grainy and watery when freezing them. If you're fine with that, go ahead and freeze the chilled soup in air-tight containers or plastic for up to three months. Reheat it slowly on the stovetop. My advice, however, is to eat it fresh.