Marshfield, United States offers 10 beaches perfect for sunbathing, surfing, swimming, and more. Marshfield, Massachusetts, United States, is known for its scenic beaches and annual Marshfield Fair. The best time to travel to Marshfield, United States, is in late spring or early fall when the average air temperature is around 60-70°F, and water temperatures are generally cool, around 50-60°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!