This is a complete list of former United States representatives whose last names begin with the letter I.
The number of years the representative/delegate has served in Congress indicates the number of terms the representative/delegate has. Note the representative/delegate can also serve non-consecutive terms if the representative/delegate loses election and wins re-election to the House.
| Representative/Delegate | Years | State/Territory | Party | Lifespan |
|---|---|---|---|---|
| Richard Howard Ichord Jr. | 1961–1981 | Missouri | Democratic | 1926–1992 |
| Santiago Iglesias | 1933–1939 | Puerto Rico | Socialist | 1872–1939 |
| James T. Igoe | 1927–1933 | Illinois | Democratic | 1883–1971 |
| Michael L. Igoe | 1935 | Illinois | Democratic | 1885–1967 |
| William L. Igoe | 1913–1921 | Missouri | Democratic | 1879–1953 |
| Peter Ihrie Jr. | 1829–1833 | Pennsylvania | Democratic | 1796–1871 |
| Frank N. Ikard | 1951–1961 | Texas | Democratic | 1913–1991 |
| George P. Ikirt | 1893–1895 | Ohio | Democratic | 1852–1927 |
| Daniel Ilsley | 1807–1809 | Massachusetts | Democratic-Republican | 1740–1813 |
| Lawrence E. Imhoff | 1933–1939 1941–1943 | Ohio | Democratic | 1895–1988 |
| James H. Imlay | 1797–1801 | New Jersey | Federalist | 1764–1823 |
| Samuel Williams Inge | 1847–1851 | Alabama | Democratic | 1817–1868 |
| William Marshall Inge | 1833–1835 | Tennessee | Democratic | 1802–1846 |
| Charles Jared Ingersoll | 1813–1815 1841–1849 | Pennsylvania | Democratic | 1782–1862 |
| Colin M. Ingersoll | 1851–1855 | Connecticut | Democratic | 1819–1903 |
| Ebon C. Ingersoll | 1864–1871 | Illinois | Republican | 1831–1879 |
| Joseph Reed Ingersoll | 1835–1837 1841–1849 | Pennsylvania | Whig | 1786–1868 |
| Ralph I. Ingersoll | 1825–1833 | Connecticut | National Republican | 1789–1872 |
| Samuel Ingham | 1835–1839 | Connecticut | Democratic | 1793–1881 |
| Samuel D. Ingham | 1813–1818 1822–1829 | Pennsylvania | Democratic-Republican | 1779–1860 |
| Bob Inglis | 1993–1999 2005–2011 | South Carolina | Republican | 1959–present |
| Jim Inhofe | 1987–1994 | Oklahoma | Republican | 1934–2024 |
| Daniel Inouye | 1959–1963 | Hawaii | Democratic | 1924–2012 |
| Jay Inslee | 1999–2012 | Washington | Democratic | 1951–present |
| Andy Ireland | 1977–1984 1984–1993 | Florida | Democratic Republican | 1930–2024 |
| Clifford C. Ireland | 1917–1923 | Illinois | Republican | 1878–1930 |
| Alfred Briggs Irion | 1885–1887 | Louisiana | Democratic | 1833–1903 |
| Alexander Irvin | 1847–1849 | Pennsylvania | Whig | 1800–1874 |
| James Irvin | 1841–1845 | Pennsylvania | Whig | 1800–1862 |
| William W. Irvin | 1829–1833 | Ohio | Democratic | 1779–1842 |
| William Irvine | 1793–1795 | Pennsylvania | Anti-Administration | 1741–1804 |
| William Irvine | 1859–1861 | New York | Republican | 1820–1882 |
| Leonard Irving | 1949–1953 | Missouri | Democratic | 1898–1962 |
| William Irving | 1814–1819 | New York | Democratic-Republican | 1766–1821 |
| Donald J. Irwin | 1959–1961 1965–1969 | Connecticut | Democratic | 1926–2013 |
| Edward M. Irwin | 1925–1931 | Illinois | Republican | 1869–1933 |
| Harvey Samuel Irwin | 1901–1903 | Kentucky | Republican | 1844–1916 |
| Jared Irwin | 1813–1817 | Pennsylvania | Democratic-Republican | 1768–1818 |
| Thomas Irwin | 1829–1831 | Pennsylvania | Democratic | 1785–1870 |
| William W. Irwin | 1841–1843 | Pennsylvania | Whig | 1803–1856 |
| Jacob C. Isacks | 1823–1825 1825–1833 | Tennessee | Democratic-Republican Democratic | 1767–1835 |
| Leo Isacson | 1948–1949 | New York | American Laborite | 1910–1996 |
| Johnny Isakson | 1999–2005 | Georgia | Republican | 1944–2021 |
| Steve Israel | 2001–2017 | New York | Democratic | 1958–present |
| Ernest Istook | 1993–2007 | Oklahoma | Republican | 1950–present |
| Anthony F. Ittner | 1877–1879 | Missouri | Republican | 1837–1931 |
| Alfred Iverson Sr. | 1847–1849 | Georgia | Democratic | 1798–1873 |
| Willard Ives | 1851–1853 | New York | Democratic | 1806–1896 |
| Edouard Izac | 1937–1947 | California | Democratic | 1891–1990 |
| James F. Izlar | 1894–1895 | South Carolina | Democratic | 1832–1912 |