December 2019
December 19: Democratic primary debate in Los Angeles

February 2020
February 3: Iowa caucuses
February 11: New Hampshire primary
February 22: Nevada Democratic caucuses
February 29: South Carolina Democratic presidential primary

March 2020
March 3 (Super Tuesday): Alabama primary, American Samoa Democratic caucuses, Arkansas primary, California primary, Colorado primary, Maine primary, Massachusetts primary, Minnesota primary, North Carolina primary, Oklahoma primary, Tennessee primary, Texas primary, Utah primary, Vermont primary, Virginia Democratic primary
March 3-10: Democrats Abroad primary
March 8: Puerto Rico Republican primary
March 10: Hawaii Republican caucuses, Idaho primary, Michigan primary, Mississippi primary, Missouri primary, North Dakota Democratic caucuses, Washington primary
March 12: Virgin Islands Republican caucuses
March 14: District of Columbia Republican caucuses, Guam Republican convention, Northern Mariana Islands Democratic convention
March 17: Arizona Democratic primary, Florida primary, Illinois primary, Ohio primary, Northern Mariana Islands Republican caucuses
March 24: American Samoa Republican caucuses, Georgia primary
March 27-29: North Dakota Republican state convention
March 29: Puerto Rico Democratic primary

April 2020
April 3-5: North Dakota Republican caucuses
April 4: Alaska Democratic caucuses, Hawaii Democratic caucuses, Louisiana primary, Wyoming Democratic caucuses
April 7: Wisconsin primary
April 28: Connecticut primary, Delaware primary, Maryland primary, New York primary, Pennsylvania primary, Rhode Island primary

May 2020
May 2: Guam Democratic caucuses, Kansas Democratic primary
May 5: Indiana primary
May 12: Nebraska primary, West Virginia primary
May 19: Kentucky primary, Oregon primary

June 2020
June 2: District of Columbia Democratic primary, Montana primary, New Jersey primary, New Mexico primary, South Dakota primary
June 6: Virgin Islands Democratic caucuses

July 2020
July 13-16: Democratic National Convention in Milwaukee, Wisconsin

August 2020
August 24-27: Republican National Convention in Charlotte, North Carolina

September 2020
September 29: First general election presidential debate at the University of Notre Dame in Notre Dame, Indiana

October 2020
October 7: Vice presidential debate at University of Utah in Salt Lake City, Utah
October 15: Second general election presidential debate at the University of Michigan in Ann Arbor, Michigan
October 22: Third general election presidential debate at Belmont University in Nashville, Tennessee

November 2020
November 3: General election