# List of former members of the United States House of Representatives (K)

This is a complete list of former members of the United States House of Representatives whose last names begin with the letter K.

## Number of years/terms representative/delegate has served

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.
* 2 years - 1 or 2 terms
* 4 years - 2 or 3 terms
* 6 years - 3 or 4 terms
* 8 years - 4 or 5 terms
* 10 years - 5 or 6 terms
* 12 years - 6 or 7 terms
* 14 years - 7 or 8 terms
* 16 years - 8 or 9 terms
* 18 years - 9 or 10 terms
* 20 years - 10 or 11 terms
* 22 years - 11 or 12 terms
* 24 years - 12 or 13 terms
* 26 years - 13 or 14 terms
* 28 years - 14 or 15 terms
* 30 years - 15 or 16 terms
* 32 years - 16 or 17 terms
* 34 years - 17 or 18 terms
* 36 years - 18 or 19 terms
* 38 years - 19 or 20 terms
* 40 years - 20 or 21 terms
* 42 years - 21 or 22 terms
* 44 years - 22 or 23 terms
* 46 years - 23 or 24 terms
* 48 years - 24 or 25 terms
* 50 years - 25 or 26 terms
* 52 years - 26 or 27 terms
* 54 years - 27 or 28 terms
* 56 years - 28 or 29 terms
* 58 years - 29 or 30 terms
| Representative/Delegate | Years | State | Party | Lifespan |
| Charles A. Kading | 1927–1933 | Wisconsin | Republican | 1874–1956 |
| Steve Kagen | 2007–2011 | Wisconsin | Democratic | 1949–present |
| Kai Kahele | 2021–2023 | Hawaii | Democratic | 1974–present |
| Florence Prag Kahn | 1925–1937 | California | Republican | 1866–1948 |
| Julius Kahn | 1899–1903 1905–1924 | California | Republican | 1861–1924 |
| Jonah Kūhiō Kalanianaʻole | 1903–1922 | Hawaii | Republican | 1871–1922 |
| Martin Kalbfleisch | 1863–1865 | New York | Democratic | 1804–1873 |
| Nicholas T. Kane | 1887 | New York | Democratic | 1846–1887 |
| Paul Kanjorski | 1985–2011 | Pennsylvania | Democratic | 1937–present |
| Charles A. Karch | 1931–1932 | Illinois | Democratic | 1875–1932 |
| Raymond W. Karst | 1949–1951 | Missouri | Democratic | 1902–1987 |
| Frank M. Karsten | 1947–1969 | Missouri | Democratic | 1913–1992 |
| Joseph Karth | 1959–1977 | Minnesota | Democratic-Farmer-Labor | 1922–2005 |
| George A. Kasem | 1959–1961 | California | Democratic | 1919–2002 |
| John Kasich | 1983–2001 | Ohio | Republican | 1952–present |
| John A. Kasson | 1863–1867 1873–1877 1881–1884 | Iowa | Republican | 1822–1910 |
| Bob Kasten | 1975–1979 | Wisconsin | Republican | 1942–present |
| Robert Kastenmeier | 1959–1991 | Wisconsin | Democratic | 1924–2015 |
| John Katko | 2015–2023 | New York | Republican | 1962–present |
| David S. Kaufman | 1846–1851 | Texas | Democratic | 1813–1851 |
| Edward Kavanagh | 1831–1835 | Maine | Democratic | 1795–1844 |
| Will Kirk Kaynor | 1929 | Massachusetts | Republican | 1884–1929 |
| Abraham Kazen | 1967–1985 | Texas | Democratic | 1919–1987 |
| John Kean | 1883–1885 1887–1889 | New Jersey | Republican | 1852–1914 |
| Robert Kean | 1939–1959 | New Jersey | Republican | 1893–1980 |
| Bernard W. Kearney | 1943–1959 | New York | Republican | 1889–1976 |
| Carroll D. Kearns | 1947–1963 | Pennsylvania | Republican | 1900–1976 |
| Charles Cyrus Kearns | 1915–1931 | Ohio | Republican | 1869–1931 |
| Edward Keating | 1913–1919 | Colorado | Democratic | 1875–1965 |
| Kenneth Keating | 1947–1959 | New York | Republican | 1900–1975 |
| William J. Keating | 1971–1974 | Ohio | Republican | 1927–2020 |
| Elizabeth Kee | 1951–1965 | West Virginia | Democratic | 1895–1975 |
| James Kee | 1965–1973 | West Virginia | Democratic | 1917–1989 |
| John Kee | 1933–1951 | West Virginia | Democratic | 1874–1951 |
| Frank Bateman Keefe | 1939–1951 | Wisconsin | Republican | 1887–1952 |
| Russell W. Keeney | 1957–1958 | Illinois | Republican | 1897–1958 |
| Richard Keese | 1827–1829 | New York | Democratic | 1794–1883 |
| Estes Kefauver | 1939–1949 | Tennessee | Democratic | 1903–1963 |
| James N. Kehoe | 1901–1905 | Kentucky | Democratic | 1862–1945 |
| Walter Kehoe | 1917–1919 | Florida | Democratic | 1870–1938 |
| Edward C. Kehr | 1875–1877 | Missouri | Democratic | 1837–1918 |
| J. Warren Keifer | 1877–1885 1905–1911 | Ohio | Republican | 1836–1932 |
| Edwin W. Keightley | 1877–1879 | Michigan | Republican | 1843–1926 |
| George M. Keim | 1838–1843 | Pennsylvania | Democratic | 1805–1861 |
| William H. Keim | 1858–1859 | Pennsylvania | Republican | 1813–1862 |
| Abraham Lincoln Keister | 1913–1917 | Pennsylvania | Republican | 1852–1917 |
| Hastings Keith | 1959–1973 | Massachusetts | Republican | 1915–2005 |
| Laurence M. Keitt | 1853–1856 1856–1860 | South Carolina | Democratic | 1824–1864 |
| John A. Keliher | 1903–1911 | Massachusetts | Democratic | 1866–1938 |
| Fred Keller | 2019–2023 | Pennsylvania | Republican | 1965–present |
| Kent E. Keller | 1931–1941 | Illinois | Democratic | 1867–1954 |
| Oscar Keller | 1919–1927 | Minnesota | Republican | 1878–1927 |
| Ric Keller | 2001–2009 | Florida | Republican | 1964–present |
| Augustine B. Kelley | 1941–1957 | Pennsylvania | Democratic | 1883–1957 |
| Harrison Kelley | 1889–1891 | Kansas | Republican | 1836–1897 |
| John Edward Kelley | 1897–1899 | South Dakota | Populist | 1853–1941 |
| Patrick H. Kelley | 1913–1923 | Michigan | Republican | 1867–1925 |
| William D. Kelley | 1861–1890 | Pennsylvania | Republican | 1814–1890 |
| Charles Kellogg | 1825–1827 | New York | Democratic | 1773–1842 |
| Francis William Kellogg | 1859–1865 | Michigan | Republican | 1810–1879 |
| Francis William Kellogg | 1868–1869 | Alabama | Republican | 1810–1879 |
| Orlando Kellogg | 1847–1849 | New York | Whig | 1809–1865 |
| Orlando Kellogg | 1863–1865 | New York | Republican | 1809–1865 |
| Stephen Kellogg | 1869–1875 | Connecticut | Republican | 1822–1904 |
| William Kellogg | 1857–1863 | Illinois | Republican | 1814–1872 |
| William Pitt Kellogg | 1883–1885 | Louisiana | Republican | 1830–1918 |
| Edna F. Kelly | 1949–1969 | New York | Democratic | 1906–1997 |
| Edward A. Kelly | 1931–1943 1945–1947 | Illinois | Democratic | 1892–1969 |
| George B. Kelly | 1937–1939 | New York | Democratic | 1900–1971 |
| James Kelly | 1805–1809 | Pennsylvania | Federalist | 1760–1819 |
| John Kelly | 1855–1858 | New York | Democratic | 1822–1886 |
| M. Clyde Kelly | 1913–1915 | Pennsylvania | Republican | 1883–1935 |
| M. Clyde Kelly | 1917–1919 | Pennsylvania | Progressive | 1883–1935 |
| M. Clyde Kelly | 1919–1935 | Pennsylvania | Republican | 1883–1935 |
| Richard Kelly | 1975–1981 | Florida | Republican | 1924–2005 |
| Sue Kelly | 1995–2007 | New York | Republican | 1936–present |
| William H. Kelsey | 1855–1857 | New York | Oppositionist | 1812–1879 |
| William H. Kelsey | 1857–1859 1867–1871 | New York | Republican | 1812–1879 |
| John R. Kelso | 1865–1867 | Missouri | Independent Republican | 1831–1891 |
| Omer M. Kem | 1891–1897 | Nebraska | Populist | 1855–1942 |
| Gouverneur Kemble | 1837–1841 | New York | Democratic | 1786–1875 |
| Bolivar E. Kemp | 1925–1933 | Louisiana | Democratic | 1871–1933 |
| Jack Kemp | 1971–1989 | New York | Republican | 1935–2009 |
| Thomas Kempshall | 1839–1841 | New York | Whig | 1795/6–1865 |
| Thomas Kenan | 1805–1811 | North Carolina | Democratic-Republican | 1771–1843 |
| Charles West Kendall | 1871–1875 | Nevada | Democratic | 1828–1914 |
| Elva R. Kendall | 1929–1931 | Kentucky | Republican | 1893–1968 |
| John W. Kendall | 1891–1892 | Kentucky | Democratic | 1834–1892 |
| Jonas Kendall | 1819–1821 | Massachusetts | Federalist | 1757–1844 |
| Joseph G. Kendall | 1829–1833 | Massachusetts | National Republican | 1788–1847 |
| Joseph M. Kendall | 1892–1893 1895–1897 | Kentucky | Democratic | 1863–1933 |
| Nathan E. Kendall | 1909–1913 | Iowa | Republican | 1868–1936 |
| Samuel Austin Kendall | 1919–1933 | Pennsylvania | Republican | 1859–1933 |
| John E. Kenna | 1877–1883 | West Virginia | Democratic | 1848–1893 |
| Ambrose Kennedy | 1913–1923 | Rhode Island | Republican | 1875–1967 |
| Ambrose Jerome Kennedy | 1932–1941 | Maryland | Democratic | 1893–1950 |
| Andrew Kennedy | 1841–1847 | Indiana | Democratic | 1810–1847 |
| Charles A. Kennedy | 1907–1921 | Iowa | Republican | 1869–1951 |
| James Kennedy | 1903–1911 | Ohio | Republican | 1853–1928 |
| John F. Kennedy | 1947–1953 | Massachusetts | Democratic | 1917–1963 |
| John L. Kennedy | 1905–1907 | Nebraska | Republican | 1854–1946 |
| John P. Kennedy | 1838–1839 1841–1845 | Maryland | Whig | 1795–1870 |
| Joseph P. Kennedy II | 1987–1999 | Massachusetts | Democratic | 1952–present |
| Joe Kennedy III | 2013–2021 | Massachusetts | Democratic | 1980–present |
| Mark Kennedy | 2001–2007 | Minnesota | Republican | 1957–present |
| Martin J. Kennedy | 1930–1945 | New York | Democratic | 1892–1955 |
| Michael J. Kennedy | 1939–1943 | New York | Democratic | 1897–1949 |
| Patrick Kennedy | 1995–2011 | Rhode Island | Democratic | 1967–present |
| Robert P. Kennedy | 1887–1891 | Ohio | Republican | 1840–1918 |
| William Kennedy | 1803–1805 1809–1811 1813–1815 | North Carolina | Democratic-Republican | 1768–1834 |
| William Kennedy | 1913–1915 | Connecticut | Democratic | 1854–1918 |
| Barbara B. Kennelly | 1982–1999 | Connecticut | Democratic | 1936–present |
| Luther Martin Kennett | 1855–1857 | Missouri | Oppositionist | 1807–1873 |
| Edward A. Kenney | 1933–1938 | New Jersey | Democratic | 1884–1938 |
| William Kennon Jr. | 1847–1849 | Ohio | Democratic | 1802–1867 |
| William Kennon Sr. | 1829–1833 1835–1837 | Ohio | Democratic | 1793–1881 |
| Everett Kent | 1923–1925 1927–1929 | Pennsylvania | Democratic | 1888–1963 |
| Joseph Kent | 1811–1815 1819–1825 | Maryland | Democratic-Republican | 1779–1837 |
| Joseph Kent | 1825–1826 | Maryland | National Republican | 1779–1837 |
| Moss Kent | 1813–1817 | New York | Federalist | 1766–1838 |
| William Kent | 1911–1913 | California | Progressive Republican | 1864–1928 |
| William Kent | 1913–1917 | California | Independent | 1864–1928 |
| William S. Kenyon | 1859–1861 | New York | Republican | 1820–1896 |
| Eugene Keogh | 1937–1967 | New York | Democratic | 1907–1989 |
| Fred J. Kern | 1901–1903 | Illinois | Democratic | 1864–1931 |
| Francis Kernan | 1863–1865 | New York | Democratic | 1816–1892 |
| Brian Kerns | 2001–2003 | Indiana | Republican | 1957–present |
| Daniel Kerr | 1887–1891 | Iowa | Republican | 1836–1916 |
| James Kerr | 1889–1891 | Pennsylvania | Democratic | 1851–1908 |
| John Kerr | 1813–1815 1815–1817 | Virginia | Democratic-Republican | 1782–1842 |
| John Bozman Kerr | 1849–1851 | Maryland | Whig | 1809–1878 |
| John H. Kerr | 1923–1953 | North Carolina | Democratic | 1873–1958 |
| John Leeds Kerr | 1825–1829 1831–1833 | Maryland | National Republican | 1780–1844 |
| John Kerr Jr. | 1853–1855 | North Carolina | Whig | 1811–1879 |
| Josiah Kerr | 1900–1901 | Maryland | Republican | 1861–1920 |
| Michael C. Kerr | 1865–1873 1875–1876 | Indiana | Democratic | 1827–1876 |
| Winfield S. Kerr | 1895–1901 | Ohio | Republican | 1852–1917 |
| James Kerrigan | 1861–1863 | New York | Independent Democrat | 1828–1899 |
| John Kershaw | 1813–1815 | South Carolina | Democratic-Republican | 1765–1829 |
| Charles J. Kersten | 1947–1949 1951–1955 | Wisconsin | Republican | 1902–1972 |
| John C. Ketcham | 1921–1933 | Michigan | Republican | 1873–1941 |
| John H. Ketcham | 1865–1873 1877–1893 1897–1906 | New York | Republican | 1832–1906 |
| Winthrop Welles Ketcham | 1875–1876 | Pennsylvania | Republican | 1820–1879 |
| William M. Ketchum | 1973–1978 | California | Republican | 1921–1978 |
| William Kettner | 1913–1921 | California | Democratic | 1864–1930 |
| John A. Key | 1913–1919 | Ohio | Democratic | 1871–1954 |
| Philip Key | 1791–1793 | Maryland | Pro-Administration | 1750–1820 |
| Philip Barton Key | 1807–1813 | Maryland | Federalist | 1757–1815 |
| Elias Keyes | 1821–1823 | Vermont | Democratic-Republican | 1758–1844 |
| Martha Keys | 1975–1979 | Kansas | Democratic | 1930–2024 |
| David Kidder | 1823–1827 | Maine | National Republican | 1787–1860 |
| Jefferson P. Kidder | 1875–1879 | Dakota | Republican | 1815–1883 |
| Zedekiah Kidwell | 1853–1857 | Virginia | Democratic | 1814–1872 |
| Andrew Kiefer | 1893–1897 | Minnesota | Republican | 1832–1904 |
| Charles E. Kiefner | 1925–1927 1929–1931 | Missouri | Republican | 1869–1942 |
| Edgar R. Kiess | 1913–1930 | Pennsylvania | Republican | 1875–1930 |
| Ruben Kihuen | 2017–2019 | Nevada | Democratic | 1980–present |
| James Kilbourne | 1813–1817 | Ohio | Democratic-Republican | 1770–1850 |
| Clarence E. Kilburn | 1940–1965 | New York | Republican | 1893–1975 |
| Paul J. Kilday | 1939–1961 | Texas | Democratic | 1900–1968 |
| Dale Kildee | 1977–2013 | Michigan | Democratic | 1929–2021 |
| Dan Kildee | 2013–2025 | Michigan | Democratic | 1958–present |
| Constantine B. Kilgore | 1887–1895 | Texas | Democratic | 1835–1897 |
| Daniel Kilgore | 1834–1838 | Ohio | Democratic | 1793–1851 |
| David Kilgore | 1857–1861 | Indiana | Republican | 1804–1879 |
| Joe M. Kilgore | 1955–1965 | Texas | Democratic | 1918–1999 |
| Joseph Kille | 1839–1841 | New Jersey | Democratic | 1790–1865 |
| John W. Killinger | 1859–1863 1871–1875 1877–1881 | Pennsylvania | Republican | 1824–1896 |
| Derek Kilmer | 2013–2025 | Washington | Democratic | 1974–present |
| Carolyn Cheeks Kilpatrick | 1997–2011 | Michigan | Democratic | 1945–present |
| Mary Jo Kilroy | 2009–2011 | Ohio | Democratic | 1949–present |
| Andy Kim | 2019–2024 | New Jersey | Democratic | 1982–present |
| Jay Kim | 1993–1999 | California | Republican | 1939–present |
| Alanson M. Kimball | 1875–1877 | Wisconsin | Republican | 1827–1913 |
| Henry M. Kimball | 1935 | Michigan | Republican | 1878–1935 |
| William P. Kimball | 1907–1909 | Kentucky | Democratic | 1857–1926 |
| William Kimmel | 1877–1881 | Maryland | Democratic | 1812–1886 |
| John Kincaid | 1829–1831 | Kentucky | Democratic | 1791–1873 |
| David Hayes Kincheloe | 1915–1930 | Kentucky | Democratic | 1877–1950 |
| Ron Kind | 1997–2023 | Wisconsin | Democratic | 1963–present |
| George John Kindel | 1913–1915 | Colorado | Democratic | 1855–1930 |
| Tom Kindness | 1975–1987 | Ohio | Republican | 1929–2004 |
| John J. Kindred | 1911–1913 1921–1929 | New York | Democratic | 1864–1937 |
| Adam King | 1827–1833 | Pennsylvania | Democratic | 1783–1835 |
| Andrew King | 1871–1873 | Missouri | Democratic | 1812–1895 |
| Austin A. King | 1863–1865 | Missouri | Unionist | 1802–1870 |
| Carleton J. King | 1961–1974 | New York | Republican | 1904–1977 |
| Cecil R. King | 1942–1969 | California | Democratic | 1898–1974 |
| Cyrus King | 1813–1817 | Massachusetts | Federalist | 1772–1817 |
| Daniel P. King | 1843–1850 | Massachusetts | Whig | 1801–1850 |
| David S. King | 1959–1963 1965–1967 | Utah | Democratic | 1917–2009 |
| Edward John King | 1915–1929 | Illinois | Republican | 1867–1929 |
| George Gordon King | 1849–1853 | Rhode Island | Whig | 1807–1870 |
| Henry King | 1831–1835 | Pennsylvania | Democratic | 1790–1861 |
| J. Floyd King | 1879–1887 | Louisiana | Democratic | 1842–1915 |
| James G. King | 1849–1851 | New Jersey | Whig | 1791–1853 |
| John King | 1831–1833 | New York | Democratic | 1775–1836 |
| John A. King | 1849–1851 | New York | Whig | 1788–1867 |
| Karl C. King | 1951–1957 | Pennsylvania | Republican | 1897–1974 |
| Perkins King | 1829–1831 | New York | Democratic | 1784–1857 |
| Peter King | 1993–2021 | New York | Republican | 1944–present |
| Preston King | 1843–1847 | New York | Democratic | 1806–1865 |
| Preston King | 1849–1853 | New York | Free Soiler | 1806–1865 |
| Rufus H. King | 1855–1857 | New York | Oppositionist | 1820–1890 |
| Samuel W. King | 1935–1943 | Hawaii | Republican | 1886–1959 |
| Steve King | 2003–2021 | Iowa | Republican | 1949–present |
| Thomas Butler King | 1839–1843 1845–1850 | Georgia | Whig | 1800–1864 |
| William H. King | 1897–1899 1900–1901 | Utah | Democratic | 1863–1949 |
| William R. King | 1811–1816 | North Carolina | Democratic-Republican | 1786–1853 |
| William S. King | 1875–1877 | Minnesota | Republican | 1828–1900 |
| William W. Kingsbury | 1857–1858 | Minnesota | Republican | 1828–1892 |
| Jack Kingston | 1993–2015 | Georgia | Republican | 1955–present |
| Moses Kinkaid | 1903–1922 | Nebraska | Republican | 1856–1922 |
| Eugene F. Kinkead | 1909–1915 | New Jersey | Democratic | 1876–1960 |
| George L. Kinnard | 1833–1836 | Indiana | Democratic | 1803–1836 |
| John F. Kinney | 1863–1865 | Utah | Democratic | 1816-1902 |
| Thomas Kinsella | 1871–1873 | New York | Democratic | 1832–1884 |
| Charles Kinsey | 1817–1819 1820–1821 | New Jersey | Democratic-Republican | 1773–1849 |
| William M. Kinsey | 1889–1891 | Missouri | Republican | 1846–1931 |
| Martin Kinsley | 1819–1821 | Massachusetts | Democratic-Republican | 1754–1835 |
| J. Roland Kinzer | 1930–1947 | Pennsylvania | Republican | 1874–1955 |
| Adam Kinzinger | 2011–2023 | Illinois | Republican | 1978–present |
| George W. Kipp | 1907–1909 1911 | Pennsylvania | Democratic | 1847–1911 |
| Andrew Jackson Kirk | 1926–1927 | Kentucky | Republican | 1866–1933 |
| Mark Kirk | 2001–2010 | Illinois | Republican | 1959–present |
| Joseph Kirkland | 1821–1823 | New York | Federalist | 1770–1844 |
| Ann Kirkpatrick | 2009–2011 2013–2017 2019–2023 | Arizona | Democratic | 1950–present |
| Littleton Kirkpatrick | 1843–1845 | New Jersey | Democratic | 1797–1859 |
| Sanford Kirkpatrick | 1913–1915 | Iowa | Democratic | 1842–1932 |
| Snyder S. Kirkpatrick | 1895–1897 | Kansas | Republican | 1848–1909 |
| William Kirkpatrick | 1807–1809 | New York | Democratic-Republican | 1769–1832 |
| William H. Kirkpatrick | 1921–1923 | Pennsylvania | Republican | 1885–1970 |
| William Sebring Kirkpatrick | 1897–1899 | Pennsylvania | Republican | 1844–1932 |
| Dorrance Kirtland | 1817–1819 | New York | Democratic-Republican | 1770–1840 |
| Michael J. Kirwan | 1937–1970 | Ohio | Democratic | 1886–1970 |
| John Kissel | 1921–1923 | New York | Republican | 1864–1938 |
| Larry Kissell | 2009–2013 | North Carolina | Democratic | 1951–present |
| Aaron Kitchell | 1791–1793 1795 | New Jersey | Pro-Administration | 1744–1820 |
| Aaron Kitchell | 1795–1797 | New Jersey | Federalist | 1744–1820 |
| Aaron Kitchell | 1799–1801 | New Jersey | Democratic-Republican | 1744–1820 |
| Bethuel Kitchen | 1867–1869 | West Virginia | Republican | 1812–1895 |
| Wade H. Kitchens | 1937–1941 | Arkansas | Democratic | 1878–1966 |
| Alvin Paul Kitchin | 1957–1963 | North Carolina | Democratic | 1908–1983 |
| Claude Kitchin | 1901–1923 | North Carolina | Democratic | 1869–1923 |
| William H. Kitchin | 1879–1881 | North Carolina | Democratic | 1837–1901 |
| William Walton Kitchin | 1897–1909 | North Carolina | Democratic | 1866–1924 |
| John W. Kittera | 1791–1795 | Pennsylvania | Pro-Administration | 1752–1801 |
| John W. Kittera | 1795–1801 | Pennsylvania | Federalist | 1752–1801 |
| Thomas Kittera | 1826–1827 | Pennsylvania | National Republican | 1789–1839 |
| George W. Kittredge | 1853–1855 | New Hampshire | Democratic | 1805–1881 |
| Richard M. Kleberg | 1931–1945 | Texas | Democratic | 1887–1955 |
| Rudolph Kleberg | 1896–1903 | Texas | Democratic | 1847–1924 |
| Jerry Kleczka | 1984–2005 | Wisconsin | Democratic | 1943–2017 |
| John C. Kleczka | 1919–1923 | Wisconsin | Republican | 1885–1959 |
| Arthur G. Klein | 1941–1945 1946–1956 | New York | Democratic | 1904–1968 |
| Herb Klein | 1993–1995 | New Jersey | Democratic | 1930–2023 |
| Ron Klein | 2007–2011 | Florida | Democratic | 1957–present |
| John J. Kleiner | 1883–1887 | Indiana | Democratic | 1845–1911 |
| Thomas S. Kleppe | 1967–1971 | North Dakota | Republican | 1919–2007 |
| Frank B. Klepper | 1905–1907 | Missouri | Republican | 1864–1933 |
| Ardolph L. Kline | 1921–1923 | New York | Republican | 1858–1930 |
| I. Clinton Kline | 1921–1923 | Pennsylvania | Republican | 1858–1947 |
| John Kline | 2003–2017 | Minnesota | Republican | 1947–present |
| Marcus C.L. Kline | 1903–1907 | Pennsylvania | Democratic | 1855–1911 |
| John Klingensmith Jr. | 1835–1839 | Pennsylvania | Democratic | 1786–1854 |
| Ron Klink | 1993–2001 | Pennsylvania | Democratic | 1951–present |
| Frank Le Blond Kloeb | 1933–1937 | Ohio | Democratic | 1890–1976 |
| Robert Klotz | 1879–1883 | Pennsylvania | Democratic | 1819–1895 |
| John C. Kluczynski | 1951–1975 | Illinois | Democratic | 1896–1975 |
| Scott L. Klug | 1991–1999 | Wisconsin | Republican | 1953–present |
| Theodore F. Kluttz | 1899–1905 | North Carolina | Democratic | 1848–1918 |
| Anthony L. Knapp | 1861–1865 | Illinois | Democratic | 1828–1881 |
| Charles Knapp | 1869–1871 | New York | Republican | 1797–1880 |
| Charles J. Knapp | 1889–1891 | New York | Republican | 1845–1916 |
| Charles L. Knapp | 1901–1911 | New York | Republican | 1847–1929 |
| Chauncey L. Knapp | 1855–1857 | Massachusetts | American | 1809–1898 |
| Chauncey L. Knapp | 1857–1859 | Massachusetts | Republican | 1809–1898 |
| Robert M. Knapp | 1873–1875 1877–1879 | Illinois | Democratic | 1831–1889 |
| Herman Knickerbocker | 1809–1811 | New York | Federalist | 1779–1855 |
| Frank C. Kniffin | 1931–1939 | Ohio | Democratic | 1894–1968 |
| C. L. Knight | 1921–1923 | Ohio | Republican | 1867–1933 |
| Jonathan Knight | 1855–1857 | Pennsylvania | Oppositionist | 1787–1858 |
| Nehemiah Knight | 1803–1808 | Rhode Island | Democratic-Republican | 1746–1808 |
| Steve Knight | 2015–2019 | California | Republican | 1966–present |
| Joe Knollenberg | 1993–2009 | Michigan | Republican | 1933–2018 |
| Philip Knopf | 1903–1909 | Illinois | Republican | 1847–1920 |
| J. Proctor Knott | 1867–1871 1875–1883 | Kentucky | Democratic | 1830–1911 |
| Joseph R. Knowland | 1903–1914 | California | Republican | 1873–1966 |
| Freeman Knowles | 1897–1899 | South Dakota | Populist | 1846–1910 |
| Ebenezer Knowlton | 1855–1857 | Maine | Oppositionist | 1815–1874 |
| James Knox | 1853–1855 | Illinois | Whig | 1807–1876 |
| James Knox | 1855–1857 | Illinois | Oppositionist | 1807–1876 |
| Samuel Knox | 1864–1865 | Missouri | Unconditional Unionist | 1815–1905 |
| Victor A. Knox | 1953–1965 | Michigan | Republican | 1899–1976 |
| William S. Knox | 1895–1903 | Massachusetts | Republican | 1843–1914 |
| Coya Knutson | 1955–1959 | Minnesota | Democratic-Farmer-Labor | 1912–1996 |
| Harold Knutson | 1917–1949 | Minnesota | Republican | 1880–1953 |
| Ed Koch | 1969–1977 | New York | Democratic | 1924–2013 |
| Leo Kocialkowski | 1933–1943 | Illinois | Democratic | 1882–1958 |
| Ray Kogovsek | 1979–1985 | Colorado | Democratic | 1941–2017 |
| Jim Kolbe | 1985–2007 | Arizona | Republican | 1942–2022 |
| Joseph P. Kolter | 1983–1993 | Pennsylvania | Democratic | 1926–2019 |
| George Konig | 1911–1913 | Maryland | Democratic | 1856–1913 |
| Ernie Konnyu | 1987–1989 | California | Republican | 1937–present |
| Thomas F. Konop | 1911–1917 | Wisconsin | Democratic | 1879–1964 |
| William H. Koontz | 1866–1869 | Pennsylvania | Republican | 1830–1911 |
| Mike Kopetski | 1991–1995 | Oregon | Democratic | 1949–present |
| Arthur W. Kopp | 1909–1913 | Wisconsin | Republican | 1874–1967 |
| William F. Kopp | 1921–1933 | Iowa | Republican | 1869–1938 |
| Herman P. Kopplemann | 1933–1939 1941–1943 1945–1947 | Connecticut | Democratic | 1880–1957 |
| Charles A. Korbly | 1909–1915 | Indiana | Democratic | 1871–1937 |
| Franklin F. Korell | 1927–1931 | Oregon | Republican | 1889–1965 |
| Horace R. Kornegay | 1961–1969 | North Carolina | Democratic | 1924–2009 |
| Suzanne Kosmas | 2009–2011 | Florida | Democratic | 1944–present |
| Peter H. Kostmayer | 1977–1981 1983–1993 | Pennsylvania | Democratic | 1946–present |
| Frank Kowalski | 1959–1963 | Connecticut | Democratic | 1907–1974 |
| Charles Kramer | 1933–1943 | California | Democratic | 1879–1943 |
| Ken Kramer | 1979–1987 | Colorado | Republican | 1942–present |
| Frank Kratovil | 2009–2011 | Maryland | Democratic | 1968–present |
| Milton Kraus | 1917–1923 | Indiana | Republican | 1866–1942 |
| Jacob Krebs | 1826–1827 | Pennsylvania | Democratic | 1782–1847 |
| John Hans Krebs | 1975–1979 | California | Democratic | 1926–2014 |
| Paul J. Krebs | 1965–1967 | New Jersey | Democratic | 1912–1996 |
| Aaron S. Kreider | 1913–1923 | Pennsylvania | Republican | 1863–1929 |
| Mike Kreidler | 1993–1995 | Washington | Democratic | 1943–present |
| George Kremer | 1823–1825 | Pennsylvania | Democratic-Republican | 1775–1854 |
| George Kremer | 1825–1829 | Pennsylvania | Democratic | 1775–1854 |
| George F. Kribbs | 1891–1895 | Pennsylvania | Democratic | 1846–1938 |
| John Kronmiller | 1909–1911 | Maryland | Republican | 1858–1928 |
| Bob Krueger | 1975–1979 | Texas | Democratic | 1935–2022 |
| Otto Krueger | 1953–1959 | North Dakota | Republican | 1890–1963 |
| Edward H. Kruse | 1949–1951 | Indiana | Democratic | 1918–2000 |
| Dennis Kucinich | 1997–2013 | Ohio | Democratic | 1946–present |
| Randy Kuhl | 2005–2009 | New York | Republican | 1943–present |
| Joseph Henry Kuhns | 1851–1853 | Pennsylvania | Whig | 1800–1883 |
| Monroe H. Kulp | 1895–1899 | Pennsylvania | Republican | 1858–1911 |
| Jacob M. Kunkel | 1857–1861 | Maryland | Democratic | 1822–1870 |
| John C. Kunkel | 1939–1951 1961–1966 | Pennsylvania | Republican | 1898–1970 |
| John Christian Kunkel | 1855–1857 | Pennsylvania | Oppositionist | 1816–1870 |
| John Christian Kunkel | 1857–1859 | Pennsylvania | Republican | 1816–1870 |
| Stanley H. Kunz | 1921–1931 1932–1933 | Illinois | Democratic | 1864–1946 |
| Theodore R. Kupferman | 1966–1969 | New York | Republican | 1920–2003 |
| J. Banks Kurtz | 1923–1935 | Pennsylvania | Republican | 1867–1960 |
| William H. Kurtz | 1851–1855 | Pennsylvania | Democratic | 1804–1868 |
| Annie Kuster | 2013–2025 | New Hampshire | Democratic | 1956–present |
| Gustav Küstermann | 1907–1911 | Wisconsin | Republican | 1850–1919 |
| Andrew J. Kuykendall | 1865–1867 | Illinois | Republican | 1815–1891 |
| Dan Kuykendall | 1967–1975 | Tennessee | Republican | 1924–2008 |
| Steven T. Kuykendall | 1999–2001 | California | Republican | 1947–2021 |
| Ole J. Kvale | 1923–1929 | Minnesota | Farmer-Labor | 1869–1929 |
| Paul J. Kvale | 1929–1939 | Minnesota | Farmer-Labor | 1896–1960 |
| John Henry Kyl | 1959–1965 1967–1973 | Iowa | Republican | 1919–2002 |
| Jon Kyl | 1987–1995 | Arizona | Republican | 1942–present |
| John C. Kyle | 1891–1897 | Mississippi | Democratic | 1851–1913 |
| Thomas B. Kyle | 1901–1905 | Ohio | Republican | 1856–1915 |
| Peter Kyros | 1967–1975 | Maine | Democratic | 1925–2012 |