There were 14 elections to the United States House of Representatives in 1889 to the 50th United States Congress and 51st United States Congress. Of these, at least 10 were special elections and 4 were general elections for new states.
One of the elections was for two seats, so the total members elected were 15.
The only gains came from new seats, created for the new states of Montana, South Dakota, North Dakota, and Washington. From these new states, 5 new Republicans were elected to the House.
Elections are listed by date and district.
|- ! | Alvin P. Hovey | | Republican | 1886 | | Incumbent resigned January 17, 1889 to become Governor of Indiana.<br/>New member elected January 29, 1889 and seated February 6, 1889.<br/>Republican hold.<br/>Winner was not elected to the next term. | nowrap |
|- ! | James N. Burnes | | Democratic | 1882 | | Incumbent died January 23, 1889.<br/>elected February 19, 1889 and seated February 25, 1889.<br/>Democratic hold.<br/>Winner was not elected to the next term; see below. | nowrap |
|- ! | James N. Burnes | | Democratic | 1882 | | Incumbent member-elect died January 23, 1889.<br/>New member elected February 19, 1889 for the term starting March 4, 1889, and was seated December 2, 1889.<br/>Democratic hold.<br/>Winner was not elected to finish the current term; see above. | nowrap |
|- ! | Richard W. Townshend | | Democratic | 1876 | | Incumbent died March 9, 1889.<br/>New member elected May 21, 1889 and seated December 2, 1889.<br/>Democratic hold. | nowrap |
|- ! | Thomas Ryan | | Republican | 1876 | | Incumbent resigned April 4, 1889 after being appointed U.S. Minister to Mexico.<br/>New member elected May 21, 1889 and seated December 2, 1889.<br/>Republican hold. | nowrap |
|- ! | Edward J. Gay | | Democratic | 1884 | | Incumbent died May 30, 1889.<br/>New member elected September 3, 1889 and seated December 2, 1889.<br/>Democratic hold. | nowrap |
|- ! | James Laird | | Republican | 1882 | | Incumbent died August 17, 1889.<br/>New member elected November 5, 1889 and seated December 2, 1889.<br/>Republican hold. | nowrap |
|- ! | Samuel S. Cox | | Democratic | 1856<br/>1864 <br/>1868<br/>1885 <br/>1886 | | Incumbent died September 10, 1889.<br/>New member elected November 5, 1889 and seated December 2, 1889.<br/>Democratic hold. | nowrap |
|- ! | Newton W. Nutting | | Republican | 1882<br/>1884 <br/>1886 | | Incumbent died October 15, 1889.<br/>New member elected November 5, 1889 and seated December 2, 1889.<br/>Republican hold. | nowrap |
|- ! | Frank T. Fitzgerald | | Democratic | 1888 | | Incumbent resigned November 4, 1889 to become Register of New York County.<br/>New member elected November 30, 1889 and seated December 9, 1889.<br/>Democratic hold. | nowrap |
|- ! | colspan=3 | None (new state) | | New seat.<br/>New member elected October 1, 1889 and seated December 2, 1889.<br/>Republican gain. | nowrap |
|- ! | colspan=3 | None (new state) | | New seat.<br/>New member elected October 1, 1889 and seated December 2, 1889.<br/>Republican gain. | nowrap |
|- ! rowspan=2 | <br> | colspan=3 | None (new state) | | New seat.<br/>New member elected October 1, 1889 and seated December 2, 1889.<br/>Republican gain. | rowspan=2 nowrap |
|- | colspan=3 | None (new state) | | New seat.<br/>New member elected October 1, 1889 and seated December 2, 1889.<br/>Republican gain.
|- ! | colspan=3 | None (new state) | | New seat.<br/>New member elected October 1, 1889 and seated December 2, 1889.<br/>Republican gain. | nowrap |