January–March
January 2 - The Standard Oil Trust (monopoly) is secretly created to control multiple corporations set up by John D. Rockefeller and his associates.
Oscar Wilde arrives in the United States for an extended lecture tour.
January 5 – Charles J. Guiteau is found guilty of the assassination of James A. Garfield (President of the United States), despite an insanity defense raised by his lawyer.
January 13 – A train collision in New York City kills eight, including Webster Wagner, a New York state senator and founder of the luxury sleeper-car company bearing his name.
March 18 – Morgan Earp is assassinated by outlaws while playing billiards in Tombstone, Arizona.
March 22 – Polygamy is made a felony by the Edmunds Act passed by the United States Congress.
March 29 – The Knights of Columbus, a Catholic fraternal service organization, is incorporated in New Haven, Connecticut by Father Michael J. McGivney.
April–June
April 3 – Old West outlaw Jesse James is shot in the back of the head and killed by fellow outlaw Robert Ford in his home at St. Joseph, Missouri for reward.
May 6 – The Chinese Exclusion Act is the first significant law that restricts immigration into the U.S.
June 30 – Charles J. Guiteau, the assassin of President James A. Garfield, is hanged.
July–September
August 3 – The U.S. Congress passes the 1882 Immigration Act.
August 5 – Standard Oil of New Jersey is established.
September 4 – Thomas Edison starts the U.S.'s first commercial electrical power plant, lighting one square mile of lower Manhattan.
September 5 – The first United States Labor Day parade is held in New York City.
September 30 – The Vulcan Street Plant, the first hydroelectric central station to serve a system of private and commercial customers in North America, comes on stream in Appleton, Wisconsin.
September – Redpath's McGee Illustrated Weekly newspaper changes its name to Redpath's Illustrated Weekly.
October–December
October 5 – The Society for Ethical Culture of Chicago (the modern-day Ethical Humanist Society of Chicago) is founded by Felix Adler.
October 16 – The New York, Chicago and St. Louis Railroad ("Nickel Plate Road") runs its first trains over the entire system between Buffalo, New York, and Chicago. Nine days later the Seney Syndicate sells the road to William Henry Vanderbilt for US$7.2 million.
November 14 – Franklyn Leslie shoots Billy Claiborne dead in the streets of Tombstone, Arizona.
December 22 – First string of Christmas lights created by Thomas Edison.