Yes, you sure can! Slice the meatloaf into portions and chill it thoroughly in the fridge for a few hours. Then, wrap it tightly in plastic wrap and then in foil. Freeze it for up to 3 months. To reheat it, thaw it in the fridge overnight then warm it wrapped in foil in a low (325-F) oven or in the microwave until warmed through. Don't overheat it or heat it too quickly or you could dry it out.