The 2021 mid-year rugby union internationals (also known as the summer internationals in the Northern Hemisphere) were a series of international rugby union matches that are typically played in the Southern Hemisphere during the July international window. Due to ongoing restrictions around the world due to the COVID-19 pandemic, a number of matches were cancelled, and some series reversed so that the Northern Hemisphere nations hosted the matches, and some teams played for the first time since their final matches of the 2019 Rugby World Cup.