The best time to go to Onset is during the summer months, particularly from late June to early September.This period offers the warmest weather, making it ideal for enjoying the beaches and outdoor activities. You'll find most local businesses, restaurants, and attractions fully operational and offering extended hours. The water in Onset Bay is also at its most pleasant for swimming and boating.Families will find this time great for a traditional seaside holiday. The warm weather means children can spend ample time at Onset Beach, building sandcastles and splashing in the calm waters of the bay. Many family-friendly events and activities, such as outdoor concerts and craft fairs, are scheduled throughout July and August.Couples looking for a relaxing escape will also appreciate the summer. You can enjoy strolls along the waterfront, dine al fresco at local restaurants, or take a scenic boat trip around the bay.