Events that occurred on 20 April.
 On Earth
- 1937 - Narrator George Takei is born.
- 1939 - Writer and screenwriter Peter S. Beagle is born.
- 1943 - J.R.R. Tolkien writes Letter 48.
- 1964 - Actor Andy Serkis is born.
- 1973 - J.R.R. Tolkien writes a letter to Dr. Denis Tolhurst.
- 1973 - J.R.R. Tolkien writes a letter to John Higgins.
- 1999 - Actor Elan Garfias is born.
- 2010 - The Lord of the Rings Online developer Turbine is bought by Warner Bros.
- 2011 - The Lord of the Rings: The Card Game was released.
- 2013 - Artist Quinton Hoover is born.
- 2015 - Voice actor Peter Howell dies.
 In Arda
- There are no known events for this day.