National Mutt Day happens every year on the 31st of July. This is a special day to recognize mixed-breed dogs, and this is an official holiday that falls on the last of July every year. The national day was created by the US Department of Agriculture, which recognized the special needs and characteristics of mutts. These four lovable dogs are often overlooked in terms of their healthcare needs, with the most common being allergy treatment. If you have a mutt, there are many things that you can do to recognize them and show support for them.