As a thank you to the cast, Will Smith divided his $40 million earnings from the movie amongst the other actors as bonuses for them.
Saniyya Sidney who is left-handed and had never played tennis before, had to learn to play like Venus Williams who is right-handed. Her grueling Mon-Fri training regime involved a strict diet and exercise, and many hours of watching videos of Venus, ranging from her victories at major tournaments like the U.S. Open and Wimbledon.
The screenplay "King Richard" was featured in the 2018 Black List, an annual list of well-received, unproduced screenplays.
Liev Schreiber was cast to play coach Paul Cohen in February 2020, but production was halted due to the COVID-19 pandemic. Filming resumed in October 2020, but Schreiber was unavailable at that time, so he was replaced by Tony Goldwyn.
Due to the pandemic, table reads were conducted on Zoom.