|} House of Representatives Replacements: 7 Democrats (D): no net change Republicans (R): 1 seat net loss Anti-Lecompton Democrats (LD): 1 seat net gain Deaths: 4 Resignations: 3 Contested election: 1 Withdrawals: 28 Total seats with changes: 41 |- | | Vacant | style="font-size:80%" | Vacancy in term | | John A. McClernand (D) | Seated November 8, 1859 |- | | Vacant | style="font-size:80%" | Brown could not take seat because he had not yet attained age required by the US Constitution | | John Y. Brown (D) | Seated December 3, 1860 |- | | | Cyrus Spink (R) | style="font-size:80%" | Died May 31, 1859 | | Harrison G. O. Blake (R) | Seated October 11, 1859 |- | | | William Goode (D) | style="font-size:80%" | Died July 3, 1859 | | Roger A. Pryor (D) | Seated December 7, 1859 |- | | | George B. Cooper (D) | style="font-size:80%" | Lost contested election May 15, 1860 | | Francis P. Blair Jr. (R) | Seated May 15, 1860 |- | | Experience Estabrook | style="font-size:80%" | Lost contested election May 18, 1860 | | Samuel G. Daily (R) | Seated May 18, 1860 |- | | | Silas M. Burroughs (R) | style="font-size:80%" | Died June 3, 1860 | | Edwin R. Reynolds (R) | Seated December 5, 1860 |- | | | John R. Barret (D) | style="font-size:80%" | Lost contested election June 8, 1860 | | William A. Howard (R) | Seated June 8, 1860 |- | | | John Schwartz (ALD) | style="font-size:80%" | Died June 20, 1860 | | Jacob K. McKenty (D) | Seated December 3, 1860 |- | | | William A. Howard (R) | style="font-size:80%" | Resigned June 25, 1860 | | John R. Barret (D) | Seated December 3, 1860 |- | | | Lucius Q. C. Lamar II (D) | style="font-size:80%" | Retired December ???, 1860 | Vacant | Not filled this term |- | | | Laurence M. Keitt (D) | style="font-size:80%" | Retired December ???, 1860 | Vacant | Not filled this term |- | | | John McQueen (D) | style="font-size:80%" | Retired December 21, 1860 | Vacant | Not filled this term |- | | | William P. Miles (D) | style="font-size:80%" | Retired December 21, 1860 | Vacant | Not filled this term |- | | | Milledge L. Bonham