January 14 - Elvis Presley's concert in Hawaii. The first worldwide telecast by an entertainer watched by more people than watched the Apollo moon landings.

January 14 – Super Bowl VII: The Miami Dolphins defeat the Washington Redskins 14–7 to complete the NFL's first Perfect Season.

January 15 – Vietnam War: Citing progress in peace negotiations, U.S. President Richard Nixon announces the suspension of offensive action in North Vietnam.

January 22 – Roe v. Wade: The U.S. Supreme Court overturns state bans on abortion.

January 23 – U.S. President Richard Nixon announces that a peace accord has been reached in Vietnam.

January 27 – U.S. involvement in the Vietnam War ends with the signing of the Paris Peace Accords.

February 11 – Vietnam War: The first American prisoners of war are released from Vietnam

February 22 – Sino-American relations: Following President Richard Nixon's visit to mainland China, the United States and the People's Republic of China agree to establish liaison offices.

February 27 – The American Indian Movement occupies Wounded Knee, South Dakota.

March 23 – Watergate scandal (United States): In a letter to Judge John Sirica, Watergate burglar James W. McCord Jr. admits that he and other defendants have been pressured to remain silent about the case. He names former Attorney General John Mitchell as 'overall boss' of the operation.

March 29 – The last United States soldier leaves Vietnam.

April 3 – The first handheld cellular phone call is made by Martin Cooper in New York City.

April 30 – Watergate scandal: President Richard Nixon announces that White House Counsel John Dean has been fired and that Attorney General Richard Kleindienst has resigned along with staffers H. R. Haldeman and John Ehrlichman.

May 8 – A 71-day standoff between federal authorities and American Indian Movement activists who were occupying the Pine Ridge Reservation at Wounded Knee, South Dakota, ends with the surrender of the militants.

May 14 – Skylab, the United States' first space station, is launched.

June 9 – Secretariat wins the Belmont Stakes by 31 lengths becoming a Triple Crown winner and breaking a 25-year hiatus since 1948.

July 1 – The United States Drug Enforcement Administration is founded.

July 2 – The United States Congress passes the Education of the Handicapped Act (EHA) mandating Special Education federally.

July 12 – 1973 National Archives Fire: A major fire destroys the entire 6th floor of the National Personnel Records Center in St. Louis, Missouri.

July 16 – Watergate Scandal: Former White House aide Alexander Butterfield informs the United States Senate Watergate Committee that President Richard Nixon had secretly recorded potentially incriminating conversations.

July 28 – Skylab 3 (Owen Garriott, Jack Lousma, Alan Bean) is launched, to conduct various medical and scientific experiments aboard Skylab.

August 15 – The U.S. bombing of Cambodia ends, officially halting 12 years of combat activity in Southeast Asia.

September 20 – The Battle of the Sexes: Billie Jean King defeats Bobby Riggs in a televised tennis match, 6–4, 6–4, 6–3, at the Astrodome in Houston, Texas.

September 22 – Henry Kissinger, United States National Security Advisor, starts his term as United States Secretary of State.

October 10 – Spiro T. Agnew resigns as Vice President of the United States and then, in federal court in Baltimore, Maryland, pleads no contest to charges of income tax evasion on $29,500 he received in 1967, while he was governor of Maryland. He is fined $10,000 and put on 3 years' probation.

October 20 – The Saturday Night Massacre: U.S. President Richard Nixon orders Attorney General Elliot Richardson to dismiss Watergate Special Prosecutor Archibald Cox. Richardson refuses and resigns, along with Deputy Attorney General William Ruckelshaus. Solicitor General Robert Bork, third in line at the Department of Justice, then fires Cox. The event raises calls for Nixon's impeachment.

November 1 – Watergate scandal: Acting Attorney General Robert Bork appoints Leon Jaworski as the new Watergate Special Prosecutor.

November 3 - Mariner program: NASA launches Mariner 10 toward Mercury (on March 29, 1974, it becomes the first space probe to reach that planet).

November 7 – The Congress of the United States overrides President Richard M. Nixon's veto of the War Powers Resolution, which limits presidential power to wage war without congressional approval.

November 16 - Skylab program: NASA launches Skylab 4 (Gerald Carr, William Pogue, Edward Gibson) from Cape Canaveral, Florida, on an 84-day mission.

November 16 - U.S. President Richard Nixon signs the Trans-Alaska Pipeline Authorization Act into law, authorizing the construction of the Alaska Pipeline.

November 17 - Watergate scandal: In Orlando, Florida, U.S. President Richard Nixon tells 400 Associated Press managing editors "I'm not a crook."

November 21 – U.S. President Richard Nixon's attorney, J. Fred Buzhardt, reveals the existence of an 18½-minute gap in one of the White House tape recordings related to Watergate.

November 27 – The United States Senate votes 92–3 to confirm Gerald Ford as Vice President of the United States.

December 16 – O.J. Simpson of the Buffalo Bills became the first running back to rush for 2,000 yards in a pro football season.

December 28 – The Endangered Species Act is passed in the United States.

 

Ongoing

• Cold War (1945–1991)

• Space Race (1957–1975)

• Vietnam War, U.S. involvement (1962–1973)

• Détente (c. 1969–1979)

• Watergate scandal (1972–1974)

• Capital punishment suspended by Furman v. Georgia (1972–1976)

• 1973 oil crisis (1973–1974)

• 1970s energy crisis (1973–1980)

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