Current delegation

Dick Durbin (D)

Tammy Duckworth (D)

Illinois was admitted to the Union on December 3, 1818, and has been represented in the United States Senate by 47 senators. Senators from Illinois are elected to class 2 and class 3.

The Senate twice refused to seat Frank L. Smith, in December 1926 for an appointed term and in March 1927 for an elected one, due to corruption, but he is included in this list because Smith and the Governor considered him to be a senator for approximately two years.

Of the eight African Americans ever to sit in the U.S. Senate since Reconstruction, three have held Illinois's class 3 seat, including Barack Obama who went on to become the president of the United States. This makes Illinois the state with the most African-American senators. Illinois's current U.S. senators are Democrats Dick Durbin (serving since 1997) and Tammy Duckworth (serving since 2017). Shelby Moore Cullom was the longest serving senator, who served from 1883 to 1913.

List of senators

Class 2 Class 2 U.S. senators belong to the electoral cycle that has recently been contested in 2002, 2008, 2014, and 2020. The next election will be in 2026.						C	Class 3 Class 3 U.S. senators belong to the electoral cycle that has recently been contested in 2004, 2010, 2016, and 2022. The next election will be in 2028.
#	Senator	Party	Dates in office	Electoral history	T		T	Electoral history	Dates in office	Party	Senator	#
1	Jesse B. Thomas	Democratic- Republican	Dec 3, 1818 – Mar 3, 1829	Elected in 1818.	1	15th	1	Elected in 1818.	Dec 3, 1818 – Mar 3, 1824	Democratic- Republican	Ninian Edwards	1
						16th	2	Re-elected in 1819. Resigned.
						17th
				Re-elected in 1823. Retired.	2	18th
									Mar 4, 1824 – Nov 24, 1824	Vacant
								Elected to finish Edwards's term. Retired.	Nov 24, 1824 – Mar 3, 1825	Democratic- Republican	John McLean	2
		National Republican				19th	3	Elected in 1825.	Mar 4, 1825 – Dec 12, 1835	Jacksonian	Elias Kane	3
						20th
2	John McLean	Jacksonian	Mar 4, 1829 – Oct 14, 1830	Elected in 1829. Died.	3	21st
Vacant			Oct 14, 1830 – Nov 12, 1830
3	David J. Baker	Jacksonian	Nov 12, 1830 – Dec 11, 1830	Appointed to continue McLean's term. Retired.
4	John M. Robinson	Jacksonian	Dec 11, 1830 – Mar 3, 1841	Elected to finish McLean's term.
						22nd	4	Re-elected in 1831. Died.
						23rd
				Re-elected in 1835. Retired.	4	24th
									Dec 12, 1835 – Dec 30, 1835	Vacant
								Appointed to finish Kane's term. Lost election to full term.	Dec 30, 1835 – Mar 3, 1837	Jacksonian	William Lee D. Ewing	4
		Democratic				25th	5	Elected in 1837. Retired.	Mar 4, 1837 – Mar 3, 1843	Democratic	Richard M. Young	5
						26th
5	Samuel McRoberts	Democratic	Mar 4, 1841 – Mar 27, 1843	Elected in 1841. Died.	5	27th
						28th	6	Elected in 1843. Lost renomination.	Mar 4, 1843 – Mar 3, 1849	Democratic	Sidney Breese	6
Vacant			Mar 27, 1843 – Aug 16, 1843
6	James Semple	Democratic	Aug 16, 1843 – Mar 3, 1847	Appointed to continue McRoberts's term. Elected in 1844 to finish McRoberts's term.[1] Retired.
						29th
7	Stephen A. Douglas	Democratic	Mar 4, 1847 – Jun 3, 1861	Elected in 1846.	6	30th
						31st	7	Elected in 1849.[2] Election voided.[a]	Mar 4, 1849 – Mar 15, 1849	Democratic	James Shields	7
									Mar 15, 1849 – Oct 27, 1849	Vacant
								Elected to finish his own term. Lost re-election.	Oct 27, 1849 – Mar 3, 1855	Democratic	James Shields
						32nd
				Re-elected in 1852.	7	33rd
						34th	8	Elected in 1855.	Mar 4, 1855 – Mar 3, 1873	Democratic	Lyman Trumbull	8
						35th				Republican
				Re-elected in 1859. Died.	8	36th
						37th	9	Re-elected in 1861.
Vacant			Jun 3, 1861 – Jun 26, 1861
8	Orville Browning	Republican	Jun 26, 1861 – Jan 12, 1863	Appointed to continue Douglas's term. Retired.
9	William A. Richardson	Democratic	Jan 12, 1863 – Mar 3, 1865	Elected to finish Douglas's term. Retired.
						38th
10	Richard Yates	Republican	Mar 4, 1865 – Mar 3, 1871	Elected in 1864 or 1865. Retired.	9	39th
						40th	10	Re-elected in 1867. [data missing]
						41st
11	John A. Logan	Republican	Mar 4, 1871 – Mar 3, 1877	Elected in 1870 or 1871. Lost re-election.	10	42nd				Liberal Republican
						43rd	11	Elected in 1873. Retired.	Mar 4, 1873 – Mar 3, 1879	Republican	Richard J. Oglesby	9
						44th
12	David Davis	Independent	Mar 4, 1877 – Mar 3, 1883	Elected in 1877. Retired.	11	45th
						46th	12	Elected in 1879.	Mar 4, 1879 – Mar 3, 1885	Republican	John A. Logan	10
						47th
13	Shelby M. Cullom	Republican	Mar 4, 1883 – Mar 3, 1913	Elected in 1882.	12	48th
						49th	13	Legislature failed to elect.	Mar 4, 1885 – May 18, 1885	Vacant
								Re-elected late in 1885. Died.	May 19, 1885 – Dec 26, 1886	Republican	John A. Logan
									Dec 26, 1886 – Jan 19, 1887	Vacant
								Elected to finish Logan's term. Retired.	Jan 19, 1887 – Mar 3, 1891	Republican	Charles Farwell	11
						50th
				Re-elected in 1888.	13	51st
						52nd	14	Elected in 1890. Retired.	Mar 4, 1891 – Mar 3, 1897	Democratic	John Palmer	12
						53rd
				Re-elected in 1894.	14	54th
						55th	15	Elected in 1897.[3] Retired.	Mar 4, 1897 – Mar 3, 1903	Republican	William Mason	13
						56th
				Re-elected in 1901.	15	57th
						58th	16	Elected in 1903. Lost re-election.	Mar 4, 1903 – Mar 3, 1909	Republican	Albert Hopkins	14
						59th
				Re-elected in 1907.[4] Lost renomination.	16	60th
						61st	17		Mar 4, 1909 – Jun 18, 1909	Vacant
								Elected in 1909, but ineligible until resignation from U.S. House. Election voided.	Jun 18, 1909 – Jul 13, 1912	Republican	William Lorimer	15
						62nd
									Jul 13, 1912 – Mar 26, 1913	Vacant
Vacant			Mar 4, 1913 – Mar 26, 1913	Legislature elected late.	17	63rd
14	J. Hamilton Lewis	Democratic	Mar 26, 1913 – Mar 3, 1919	Elected late in 1913. Lost re-election.				Elected in 1913 to finish Lorimer's term.	Mar 26, 1913 – Mar 3, 1921	Republican	Lawrence Y. Sherman	16
						64th	18	Re-elected in 1914. Retired.
						65th
15	Medill McCormick	Republican	Mar 4, 1919 – Feb 25, 1925	Elected in 1918. Lost renomination and died just before the end of the term.	18	66th
						67th	19	Elected in 1920. Lost renomination and died just before the end of the term.	Mar 4, 1921 – Dec 7, 1926	Republican	William B. McKinley	17
						68th
16	Charles S. Deneen	Republican	Feb 26, 1925 – Mar 3, 1931	Appointed to finish McCormick's term, having already been elected to the next term.
				Elected in 1924. Lost renomination.	19	69th
								Appointed to continue McKinley's term. Not seated/resigned.[b]	Dec 7, 1926	Republican	Frank L. Smith	18
									Dec 7, 1926 – Dec 3, 1928	Vacant
						70th	20
								Elected to finish the term. Lost re-election.	Dec 3, 1928 – Mar 3, 1933	Republican	Otis F. Glenn	19
						71st
17	J. Hamilton Lewis	Democratic	Mar 4, 1931 – Apr 9, 1939	Elected in 1930.	20	72nd
						73rd	21	Elected in 1932. Retired.	Mar 4, 1933 – Jan 3, 1939	Democratic	William H. Dieterich	20
						74th
				Re-elected in 1936. Died.	21	75th
						76th	22	Elected in 1938.	Jan 3, 1939 – Jan 3, 1951	Democratic	Scott W. Lucas	21
Vacant			Apr 9, 1939 – Apr 14, 1939
18	James M. Slattery	Democratic	Apr 14, 1939 – Nov 21, 1940	Appointed to continue Lewis's term. Lost election to finish Lewis's term.
19	C. Wayland Brooks	Republican	Nov 22, 1940 – Jan 3, 1949	Elected to finish Lewis's term.
						77th
				Re-elected in 1942. Lost re-election.	22	78th
						79th	23	Re-elected in 1944. Lost re-election.
						80th
20	Paul Douglas	Democratic	Jan 3, 1949 – Jan 3, 1967	Elected in 1948.	23	81st
						82nd	24	Elected in 1950.	Jan 3, 1951 – Sep 7, 1969	Republican	Everett Dirksen	22
						83rd
				Re-elected in 1954.	24	84th
						85th	25	Re-elected in 1956.
						86th
				Re-elected in 1960. Lost re-election.	25	87th
						88th	26	Re-elected in 1962.
						89th
21	Charles H. Percy	Republican	Jan 3, 1967 – Jan 3, 1985	Elected in 1966.	26	90th
						91st	27	Re-elected in 1968. Died.
									Sep 7, 1969 – Sep 17, 1969	Vacant
								Appointed to continue Dirksen's term. Lost election to finish Dirksen's term.	Sep 17, 1969 – Nov 3, 1970	Republican	Ralph T. Smith	23
									Nov 3, 1970 – Nov 17, 1970	Vacant
								Elected to finish Dirksen's term.	Nov 17, 1970 – Jan 3, 1981	Democratic	Adlai Stevenson III	24
						92nd
				Re-elected in 1972.	27	93rd
						94th	28	Re-elected in 1974. Retired.
						95th
				Re-elected in 1978. Lost re-election.	28	96th
						97th	29	Elected in 1980.	Jan 3, 1981 – Jan 3, 1993	Democratic	Alan J. Dixon	25
						98th
22	Paul Simon	Democratic	Jan 3, 1985 – Jan 3, 1997	Elected in 1984.	29	99th
						100th	30	Re-elected in 1986. Lost renomination.
						101st
				Re-elected in 1990. Retired.	30	102nd
						103rd	31	Elected in 1992. Lost re-election.	Jan 3, 1993 – Jan 3, 1999	Democratic	Carol Moseley Braun	26
						104th
23	Dick Durbin	Democratic	Jan 3, 1997 – present	Elected in 1996.	31	105th
						106th	32	Elected in 1998. Retired.	Jan 3, 1999 – Jan 3, 2005	Republican	Peter Fitzgerald	27
						107th
				Re-elected in 2002.	32	108th
						109th	33	Elected in 2004. Resigned to become U.S. President.	Jan 3, 2005 – Nov 16, 2008	Democratic	Barack Obama	28
						110th
									Nov 16, 2008 – Jan 12, 2009	Vacant
				Re-elected in 2008.	33	111th
								Appointed to continue Obama's term, certified late. Retired when successor qualified.	Jan 12, 2009– Nov 29, 2010	Democratic	Roland Burris	29
								Elected to finish Obama's term.[c]	Nov 29, 2010 – Jan 3, 2017	Republican	Mark Kirk	30
						112th	34	Elected to full term in 2010.[c] Lost re-election.
						113th
				Re-elected in 2014.	34	114th
						115th	35	Elected in 2016.	Jan 3, 2017 – present	Democratic	Tammy Duckworth	31
						116th
				Re-elected in 2020.	35	117th
						118th	36	Re-elected in 2022.
						119th
To be determined in the 2026 election.					36	120th
						121st	37	To be determined in the 2028 election.
#	Senator	Party	Years in office	Electoral history	T	C	T	Electoral history	Years in office	Party	Senator	#
Class 2							Class 3