The 2021 Hall of Fame Open was a men's tennis tournament played on outdoor grass courts.

It was the 45th edition of the event, and part of the 250 series of the 2021 ATP Tour.

It took place at the International Tennis Hall of Fame in Newport, Rhode Island, United States, from July 12 through July 18, 2021.

[1] *per team The following players received wildcards into the main draw: The following players received entry from the qualifying draw: The following pairs received wildcards into the doubles main draw: The following pair received entry as alternates: