# United States congressional delegations from Iowa

Since Iowa became a U.S. state in 1846, it has sent congressional delegations to the United States Senate and United States House of Representatives. Each state elects two senators to serve for six years, and members of the House to two-year terms. Before becoming a state, the Iowa Territory elected a non-voting delegate at-large to Congress from 1838 to 1846.
These are tables of congressional delegations from Iowa to the United States Senate and the United States House of Representatives.

## Current delegation

Current U.S. senators from Iowa :
| Iowa CPVI (2022): R+6 | Class II senator | Class III senator |
| Iowa CPVI (2022): R+6 | Joni Ernst (Junior senator) (Red Oak) | Chuck Grassley (Senior senator) (New Hartford) |
| Party | Republican | Republican |
| Incumbent since | January 3, 2015 | January 3, 1981 |
Iowa's current congressional delegation in the 119th Congress consists of its two senators and four representatives, all Republicans.
The current dean of the Iowa delegation is Senator and President pro tempore of the United States Senate Chuck Grassley, having served in the Senate since 1981 and in Congress since 1975.
Current U.S. representatives from Iowa :
| District | Member (Residence) | Party | Incumbent since | CPVI (2022) |
| 1st | Mariannette Miller-Meeks (LeClaire) | Republican | January 3, 2021 | R+3 |
| 2nd | Ashley Hinson (Marion) | Republican | January 3, 2021 | R+4 |
| 3rd | Zach Nunn (Bondurant) | Republican | January 3, 2023 | R+3 |
| 4th | Randy Feenstra (Hull) | Republican | January 3, 2021 | R+16 |

## United States Senate

| Class II senator | Congress | Class III senator |
| George Wallace Jones (D) | 30th (1847–1849) | Augustus C. Dodge (D) |
| George Wallace Jones (D) | 31st (1849–1851) | Augustus C. Dodge (D) |
| George Wallace Jones (D) | 32nd (1851–1853) | Augustus C. Dodge (D) |
| George Wallace Jones (D) | 33rd (1853–1855) | Augustus C. Dodge (D) |
| George Wallace Jones (D) | 34th (1855–1857) | James Harlan (R) |
| George Wallace Jones (D) | 35th (1857–1859) | James Harlan (R) |
| James W. Grimes (R) | 36th (1859–1861) | James Harlan (R) |
| James W. Grimes (R) | 37th (1861–1863) | James Harlan (R) |
| James W. Grimes (R) | 38th (1863–1865) | James Harlan (R) |
| James W. Grimes (R) | 39th (1865–1867) | James Harlan (R) |
| James W. Grimes (R) | 39th (1865–1867) | Samuel J. Kirkwood (R) |
| James W. Grimes (R) | 40th (1867–1869) | James Harlan (R) |
| James W. Grimes (R) | 41st (1869–1871) | James Harlan (R) |
| James B. Howell (R) | 41st (1869–1871) | James Harlan (R) |
| George G. Wright (R) | 42nd (1871–1873) | James Harlan (R) |
| George G. Wright (R) | 43rd (1873–1875) | William B. Allison (R) |
| George G. Wright (R) | 44th (1875–1877) | William B. Allison (R) |
| Samuel J. Kirkwood (R) | 45th (1877–1879) | William B. Allison (R) |
| Samuel J. Kirkwood (R) | 46th (1879–1881) | William B. Allison (R) |
| Samuel J. Kirkwood (R) | 47th (1881–1883) | William B. Allison (R) |
| James W. McDill (R) | 47th (1881–1883) | William B. Allison (R) |
| James F. Wilson (R) | 48th (1883–1885) | William B. Allison (R) |
| James F. Wilson (R) | 49th (1885–1887) | William B. Allison (R) |
| James F. Wilson (R) | 50th (1887–1889) | William B. Allison (R) |
| James F. Wilson (R) | 51st (1889–1891) | William B. Allison (R) |
| James F. Wilson (R) | 52nd (1891–1893) | William B. Allison (R) |
| James F. Wilson (R) | 53rd (1893–1895) | William B. Allison (R) |
| John H. Gear (R) | 54th (1895–1897) | William B. Allison (R) |
| John H. Gear (R) | 55th (1897–1899) | William B. Allison (R) |
| John H. Gear (R) | 56th (1899–1901) | William B. Allison (R) |
| Jonathan P. Dolliver (R) | 56th (1899–1901) | William B. Allison (R) |
| Jonathan P. Dolliver (R) | 57th (1901–1903) | William B. Allison (R) |
| Jonathan P. Dolliver (R) | 58th (1903–1905) | William B. Allison (R) |
| Jonathan P. Dolliver (R) | 59th (1905–1907) | William B. Allison (R) |
| Jonathan P. Dolliver (R) | 60th (1907–1909) | William B. Allison (R) |
| Jonathan P. Dolliver (R) | 60th (1907–1909) | Albert B. Cummins (R) |
| Jonathan P. Dolliver (R) | 61st (1909–1911) | Albert B. Cummins (R) |
| Lafayette Young (R) | 61st (1909–1911) | Albert B. Cummins (R) |
| Lafayette Young (R) | 62nd (1911–1913) | Albert B. Cummins (R) |
| William S. Kenyon (R) | 62nd (1911–1913) | Albert B. Cummins (R) |
| William S. Kenyon (R) | 63rd (1913–1915) | Albert B. Cummins (R) |
| William S. Kenyon (R) | 64th (1915–1917) | Albert B. Cummins (R) |
| William S. Kenyon (R) | 65th (1917–1919) | Albert B. Cummins (R) |
| William S. Kenyon (R) | 66th (1919–1921) | Albert B. Cummins (R) |
| William S. Kenyon (R) | 67th (1921–1923) | Albert B. Cummins (R) |
| Charles A. Rawson (R) | 67th (1921–1923) | Albert B. Cummins (R) |
| Smith W. Brookhart (R) | 67th (1921–1923) | Albert B. Cummins (R) |
| Smith W. Brookhart (R) | 68th (1923–1925) | Albert B. Cummins (R) |
| Smith W. Brookhart (R) | 69th (1925–1927) | Albert B. Cummins (R) |
| Daniel F. Steck (D) | 69th (1925–1927) | David W. Stewart (R) |
| Daniel F. Steck (D) | 70th (1927–1929) | Smith W. Brookhart (R) |
| Daniel F. Steck (D) | 71st (1929–1931) | Smith W. Brookhart (R) |
| L. J. Dickinson (R) | 72nd (1931–1933) | Smith W. Brookhart (R) |
| L. J. Dickinson (R) | 73rd (1933–1935) | Louis Murphy (D) |
| L. J. Dickinson (R) | 74th (1935–1937) | Louis Murphy (D) |
| L. J. Dickinson (R) | 74th (1935–1937) | Guy Gillette (D) |
| Clyde L. Herring (D) | 75th (1937–1939) | Guy Gillette (D) |
| Clyde L. Herring (D) | 76th (1939–1941) | Guy Gillette (D) |
| Clyde L. Herring (D) | 77th (1941–1943) | Guy Gillette (D) |
| George A. Wilson (R) | 78th (1943–1945) | Guy Gillette (D) |
| George A. Wilson (R) | 79th (1945–1947) | Bourke B. Hickenlooper (R) |
| George A. Wilson (R) | 80th (1947–1949) | Bourke B. Hickenlooper (R) |
| Guy Gillette (D) | 81st (1949–1951) | Bourke B. Hickenlooper (R) |
| Guy Gillette (D) | 82nd (1951–1953) | Bourke B. Hickenlooper (R) |
| Guy Gillette (D) | 83rd (1953–1955) | Bourke B. Hickenlooper (R) |
| Thomas E. Martin (R) | 84th (1955–1957) | Bourke B. Hickenlooper (R) |
| Thomas E. Martin (R) | 85th (1957–1959) | Bourke B. Hickenlooper (R) |
| Thomas E. Martin (R) | 86th (1959–1961) | Bourke B. Hickenlooper (R) |
| Jack Miller (R) | 87th (1961–1963) | Bourke B. Hickenlooper (R) |
| Jack Miller (R) | 88th (1963–1965) | Bourke B. Hickenlooper (R) |
| Jack Miller (R) | 89th (1965–1967) | Bourke B. Hickenlooper (R) |
| Jack Miller (R) | 90th (1967–1969) | Bourke B. Hickenlooper (R) |
| Jack Miller (R) | 91st (1969–1971) | Harold Hughes (D) |
| Jack Miller (R) | 92nd (1971–1973) | Harold Hughes (D) |
| Dick Clark (D) | 93rd (1973–1975) | Harold Hughes (D) |
| Dick Clark (D) | 94th (1975–1977) | John Culver (D) |
| Dick Clark (D) | 95th (1977–1979) | John Culver (D) |
| Roger Jepsen (R) | 96th (1979–1981) | John Culver (D) |
| Roger Jepsen (R) | 97th (1981–1983) | Chuck Grassley (R) |
| Roger Jepsen (R) | 98th (1983–1985) | Chuck Grassley (R) |
| Tom Harkin (D) | 99th (1985–1987) | Chuck Grassley (R) |
| Tom Harkin (D) | 100th (1987–1989) | Chuck Grassley (R) |
| Tom Harkin (D) | 101st (1989–1991) | Chuck Grassley (R) |
| Tom Harkin (D) | 102nd (1991–1993) | Chuck Grassley (R) |
| Tom Harkin (D) | 103rd (1993–1995) | Chuck Grassley (R) |
| Tom Harkin (D) | 104th (1995–1997) | Chuck Grassley (R) |
| Tom Harkin (D) | 105th (1997–1999) | Chuck Grassley (R) |
| Tom Harkin (D) | 106th (1999–2001) | Chuck Grassley (R) |
| Tom Harkin (D) | 107th (2001–2003) | Chuck Grassley (R) |
| Tom Harkin (D) | 108th (2003–2005) | Chuck Grassley (R) |
| Tom Harkin (D) | 109th (2005–2007) | Chuck Grassley (R) |
| Tom Harkin (D) | 110th (2007–2009) | Chuck Grassley (R) |
| Tom Harkin (D) | 111th (2009–2011) | Chuck Grassley (R) |
| Tom Harkin (D) | 112th (2011–2013) | Chuck Grassley (R) |
| Tom Harkin (D) | 113th (2013–2015) | Chuck Grassley (R) |
| Joni Ernst (R) | 114th (2015–2017) | Chuck Grassley (R) |
| Joni Ernst (R) | 115th (2017–2019) | Chuck Grassley (R) |
| Joni Ernst (R) | 116th (2019–2021) | Chuck Grassley (R) |
| Joni Ernst (R) | 117th (2021–2023) | Chuck Grassley (R) |
| Joni Ernst (R) | 118th (2023–2025) | Chuck Grassley (R) |
| Joni Ernst (R) | 119th (2025–2027) | Chuck Grassley (R) |

## United States House of Representatives
### 1838–1846: 1 non-voting delegate

On July 4, 1838, the Iowa Territory was organized. Most of the area comprising the territory was originally part of the Louisiana Purchase and was a part of the Missouri Territory. When Missouri became a state in 1821, this area (along with the Dakotas) effectively became unorganized territory. The area was closed to white settlers until the 1830s, after the Black Hawk War ended. It was attached to the Michigan Territory on June 28, 1834, and was split off with the Wisconsin Territory in 1836 when Michigan became a state. The Iowa Territory was the "Iowa District" of western Wisconsin Territory – the region west of the Mississippi River. The original boundaries of the territory, as established in 1838, included part of Minnesota and parts of the Dakotas, covering about 194,000 square miles (500,000 km$^2$) of land.
Starting on September 10, 1838, Iowa Territory sent a non-voting delegate to the House.
| Years | Delegate from Territory's at-large district |
| September 10, 1838 – October 27, 1840 | William W. Chapman (D) |
| October 28, 1840 – December 28, 1846 | Augustus C. Dodge (D) |

### 1846–1863: 2 seats

Following statehood on December 28, 1846, Iowa had two seats in the House. It elected both seats statewide at-large on a general ticket, until 1847, when it redistricted into two districts.
| Congress | Elected on a general ticket | Elected on a general ticket |
| Congress | 1st seat | 2nd seat |
| 29th (1845–1847) | Serranus C. Hastings (D) | Shepherd Leffler (D) |
| Congress | 1st district | 2nd district |
| 30th (1847–1849) | William Thompson (D) | Shepherd Leffler (D) |
| 31st (1849–1851) | William Thompson (D) | Shepherd Leffler (D) |
| 31st (1849–1851) | Daniel F. Miller (W) | Shepherd Leffler (D) |
| 32nd (1851–1853) | Bernhart Henn (D) | Lincoln Clark (D) |
| 33rd (1853–1855) | Bernhart Henn (D) | John Parsons Cook (W) |
| 34th (1855–1857) | Augustus Hall (D) | James Thorington (W) |
| 35th (1857–1859) | Samuel Ryan Curtis (R) | Timothy Davis (R) |
| 36th (1859–1861) | Samuel Ryan Curtis (R) | William Vandever (R) |
| 37th (1861–1863) | Samuel Ryan Curtis (R) | William Vandever (R) |
| 37th (1861–1863) | James F. Wilson (R) | William Vandever (R) |

### 1863–1873: 6 seats

Following the 1860 census, Iowa was apportioned 6 seats.
| Congress | 1st district | 2nd district | 3rd district | 4th district | 5th district | 6th district |
| 38th (1863–1865) | James F. Wilson (R) | Hiram Price (R) | William B. Allison (R) | Josiah B. Grinnell (R) | John A. Kasson (R) | Asahel W. Hubbard (R) |
| 39th (1865–1867) | James F. Wilson (R) | Hiram Price (R) | William B. Allison (R) | Josiah B. Grinnell (R) | John A. Kasson (R) | Asahel W. Hubbard (R) |
| 40th (1867–1869) | James F. Wilson (R) | Hiram Price (R) | William B. Allison (R) | William Loughridge (R) | Grenville M. Dodge (R) | Asahel W. Hubbard (R) |
| 41st (1869–1871) | George W. McCrary (R) | William Smyth (R) | William B. Allison (R) | William Loughridge (R) | Francis W. Palmer (R) | Charles Pomeroy (R) |
| 41st (1869–1871) | George W. McCrary (R) | William P. Wolf (R) | William B. Allison (R) | William Loughridge (R) | Francis W. Palmer (R) | Charles Pomeroy (R) |
| 42nd (1871–1873) | George W. McCrary (R) | Aylett R. Cotton (R) | William G. Donnan (R) | Madison M. Walden (R) | Francis W. Palmer (R) | Jackson Orr (R) |

### 1873–1883: 9 seats

Following the 1870 census, Iowa was apportioned 9 seats.
| Congress | 1st district | 2nd district | 3rd district | 4th district | 5th district | 6th district | 7th district | 8th district | 9th district |
| 43rd (1873–1875) | George W. McCrary (R) | Aylett R. Cotton (R) | William G. Donnan (R) | Henry Otis Pratt (R) | James Wilson (R) | William Loughridge (R) | John A. Kasson (R) | James W. McDill (R) | Jackson Orr (R) |
| 44th (1875–1877) | George W. McCrary (R) | John Q. Tufts (R) | L. L. Ainsworth (D) | Henry Otis Pratt (R) | James Wilson (R) | Ezekiel S. Sampson (R) | John A. Kasson (R) | James W. McDill (R) | S. Addison Oliver (R) |
| 45th (1877–1879) | Joseph Champlin Stone (R) | Hiram Price (R) | Theodore Weld Burdick (R) | Nathaniel Cobb Deering (R) | Rush Clark (R) | Ezekiel S. Sampson (R) | Henry J. B. Cummings (R) | William Fletcher Sapp (R) | S. Addison Oliver (R) |
| 46th (1879–1881) | Moses A. McCoid (R) | Hiram Price (R) | Thomas Updegraff (R) | Nathaniel Cobb Deering (R) | Rush Clark (R) | James B. Weaver (GB) | Edward H. Gillette (GB) | William Fletcher Sapp (R) | Cyrus C. Carpenter (R) |
| 46th (1879–1881) | Moses A. McCoid (R) | Hiram Price (R) | Thomas Updegraff (R) | Nathaniel Cobb Deering (R) | William George Thompson (R) | James B. Weaver (GB) | Edward H. Gillette (GB) | William Fletcher Sapp (R) | Cyrus C. Carpenter (R) |
| 47th (1881–1883) | Moses A. McCoid (R) | Sewall S. Farwell (R) | Thomas Updegraff (R) | Nathaniel Cobb Deering (R) | William George Thompson (R) | Marsena E. Cutts (R) | John A. Kasson (R) | William P. Hepburn (R) | Cyrus C. Carpenter (R) |
| 47th (1881–1883) | Moses A. McCoid (R) | Sewall S. Farwell (R) | Thomas Updegraff (R) | Nathaniel Cobb Deering (R) | William George Thompson (R) | John C. Cook (D) | John A. Kasson (R) | William P. Hepburn (R) | Cyrus C. Carpenter (R) |

### 1883–1933: 11 seats

Following the 1880 census, Iowa was apportioned 11 seats.
| Congress | District | District | District | District | District | District | District | District | District | District | District |
| Congress | 1st | 2nd | 3rd | 4th | 5th | 6th | 7th | 8th | 9th | 10th | 11th |
| 48th (1883–1885) | Moses A. McCoid (R) | Jeremiah H. Murphy (D) | David B. Henderson (R) | Luman Hamlin Weller (GB) | Jim Wilson (R) | Marsena E. Cutts (R) | John A. Kasson (R) | William P. Hepburn (R) | William H. M. Pusey (D) | Adoniram J. Holmes (R) | Isaac S. Struble (R) |
| 48th (1883–1885) | Moses A. McCoid (R) | Jeremiah H. Murphy (D) | David B. Henderson (R) | Luman Hamlin Weller (GB) | Benjamin T. Frederick (D) | John Cook (D) | Hiram Smith (R) | William P. Hepburn (R) | William H. M. Pusey (D) | Adoniram J. Holmes (R) | Isaac S. Struble (R) |
| 49th (1885–1887) | Ben Hall (D) | Jeremiah H. Murphy (D) | David B. Henderson (R) | William E. Fuller (R) | Benjamin T. Frederick (D) | James B. Weaver (GB) | Edwin H. Conger (R) | William P. Hepburn (R) | Joseph Lyman (R) | Adoniram J. Holmes (R) | Isaac S. Struble (R) |
| 50th (1887–1889) | John H. Gear (R) | Walter I. Hayes (D) | David B. Henderson (R) | William E. Fuller (R) | Daniel Kerr (R) | James B. Weaver (GB) | Edwin H. Conger (R) | Albert R. Anderson (IR) | Joseph Lyman (R) | Adoniram J. Holmes (R) | Isaac S. Struble (R) |
| 51st (1889–1891) | John H. Gear (R) | Walter I. Hayes (D) | David B. Henderson (R) | Joseph Henry Sweney (R) | Daniel Kerr (R) | John F. Lacey (R) | Edwin H. Conger (R) | James P. Flick (R) | Joseph Rea Reed (R) | Jonathan P. Dolliver (R) | Isaac S. Struble (R) |
| 51st (1889–1891) | John H. Gear (R) | Walter I. Hayes (D) | David B. Henderson (R) | Joseph Henry Sweney (R) | Daniel Kerr (R) | John F. Lacey (R) | Edward Hays (R) | James P. Flick (R) | Joseph Rea Reed (R) | Jonathan P. Dolliver (R) | Isaac S. Struble (R) |
| 52nd (1891–1893) | John J. Seerley (D) | Walter I. Hayes (D) | David B. Henderson (R) | Walter H. Butler (D) | John Taylor Hamilton (D) | Frederick E. White (D) | John A. T. Hull (R) | James P. Flick (R) | Thomas Bowman (D) | Jonathan P. Dolliver (R) | George D. Perkins (R) |
| 53rd (1893–1895) | John Gear (R) | Walter I. Hayes (D) | David B. Henderson (R) | Thomas Updegraff (R) | Robert G. Cousins (R) | John F. Lacey (R) | John A. T. Hull (R) | William P. Hepburn (R) | Alva L. Hager (R) | Jonathan P. Dolliver (R) | George D. Perkins (R) |
| 54th (1895–1897) | Samuel M. Clark (R) | George M. Curtis (R) | David B. Henderson (R) | Thomas Updegraff (R) | Robert G. Cousins (R) | John F. Lacey (R) | John A. T. Hull (R) | William P. Hepburn (R) | Alva L. Hager (R) | Jonathan P. Dolliver (R) | George D. Perkins (R) |
| 55th (1897–1899) | Samuel M. Clark (R) | George M. Curtis (R) | David B. Henderson (R) | Thomas Updegraff (R) | Robert G. Cousins (R) | John F. Lacey (R) | John A. T. Hull (R) | William P. Hepburn (R) | Alva L. Hager (R) | Jonathan P. Dolliver (R) | George D. Perkins (R) |
| 56th (1899–1901) | Thomas Hedge (R) | Joe Lane (R) | David B. Henderson (R) | Gilbert N. Haugen (R) | Robert G. Cousins (R) | John F. Lacey (R) | John A. T. Hull (R) | William P. Hepburn (R) | Smith McPherson (R) | Jonathan P. Dolliver (R) | Lot Thomas (R) |
| 56th (1899–1901) | Thomas Hedge (R) | Joe Lane (R) | David B. Henderson (R) | Gilbert N. Haugen (R) | Robert G. Cousins (R) | John F. Lacey (R) | John A. T. Hull (R) | William P. Hepburn (R) | Walter I. Smith (R) | James P. Conner (R) | Lot Thomas (R) |
| 57th (1901–1903) | Thomas Hedge (R) | John Rumple (R) | David B. Henderson (R) | Gilbert N. Haugen (R) | Robert G. Cousins (R) | John F. Lacey (R) | John A. T. Hull (R) | William P. Hepburn (R) | Walter I. Smith (R) | James P. Conner (R) | Lot Thomas (R) |
| 58th (1903–1905) | Thomas Hedge (R) | Martin Wade (D) | Benjamin P. Birdsall (R) | Gilbert N. Haugen (R) | Robert G. Cousins (R) | John F. Lacey (R) | John A. T. Hull (R) | William P. Hepburn (R) | Walter I. Smith (R) | James P. Conner (R) | Lot Thomas (R) |
| 59th (1905–1907) | Thomas Hedge (R) | Albert F. Dawson (R) | Benjamin P. Birdsall (R) | Gilbert N. Haugen (R) | Robert G. Cousins (R) | John F. Lacey (R) | John A. T. Hull (R) | William P. Hepburn (R) | Walter I. Smith (R) | James P. Conner (R) | Elbert H. Hubbard (R) |
| 60th (1907–1909) | Charles A. Kennedy (R) | Albert F. Dawson (R) | Benjamin P. Birdsall (R) | Gilbert N. Haugen (R) | Robert G. Cousins (R) | Daniel W. Hamilton (D) | John A. T. Hull (R) | William P. Hepburn (R) | Walter I. Smith (R) | James P. Conner (R) | Elbert H. Hubbard (R) |
| 61st (1909–1911) | Charles A. Kennedy (R) | Albert F. Dawson (R) | Charles E. Pickett (R) | Gilbert N. Haugen (R) | James W. Good (R) | Nathan E. Kendall (R) | John A. T. Hull (R) | William Darius Jamieson (D) | Walter I. Smith (R) | Frank P. Woods (R) | Elbert H. Hubbard (R) |
| 62nd (1911–1913) | Charles A. Kennedy (R) | Irvin S. Pepper (D) | Charles E. Pickett (R) | Gilbert N. Haugen (R) | James W. Good (R) | Nathan E. Kendall (R) | Solomon F. Prouty (R) | Horace M. Towner (R) | Walter I. Smith (R) | Frank P. Woods (R) | Elbert H. Hubbard (R) |
| 62nd (1911–1913) | Charles A. Kennedy (R) | Irvin S. Pepper (D) | Charles E. Pickett (R) | Gilbert N. Haugen (R) | James W. Good (R) | Nathan E. Kendall (R) | Solomon F. Prouty (R) | Horace M. Towner (R) | William R. Green (R) | Frank P. Woods (R) | George C. Scott (R) |
| 63rd (1913–1915) | Charles A. Kennedy (R) | Irvin S. Pepper (D) | Maurice Connolly (D) | Gilbert N. Haugen (R) | James W. Good (R) | Sanford Kirkpatrick (D) | Solomon F. Prouty (R) | Horace M. Towner (R) | William R. Green (R) | Frank P. Woods (R) | George C. Scott (R) |
| 63rd (1913–1915) | Charles A. Kennedy (R) | Henry Vollmer (D) | Maurice Connolly (D) | Gilbert N. Haugen (R) | James W. Good (R) | Sanford Kirkpatrick (D) | Solomon F. Prouty (R) | Horace M. Towner (R) | William R. Green (R) | Frank P. Woods (R) | George C. Scott (R) |
| 64th (1915–1917) | Charles A. Kennedy (R) | Harry E. Hull (R) | Burton E. Sweet (R) | Gilbert N. Haugen (R) | James W. Good (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Horace M. Towner (R) | William R. Green (R) | Frank P. Woods (R) | Thomas J. Steele (D) |
| 65th (1917–1919) | Charles A. Kennedy (R) | Harry E. Hull (R) | Burton E. Sweet (R) | Gilbert N. Haugen (R) | James W. Good (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Horace M. Towner (R) | William R. Green (R) | Frank P. Woods (R) | George C. Scott (R) |
| 66th (1919–1921) | Charles A. Kennedy (R) | Harry E. Hull (R) | Burton E. Sweet (R) | Gilbert N. Haugen (R) | James W. Good (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Horace M. Towner (R) | William R. Green (R) | L. J. Dickinson (R) | William D. Boies (R) |
| 67th (1921–1923) | William F. Kopp (R) | Harry E. Hull (R) | Burton E. Sweet (R) | Gilbert N. Haugen (R) | James W. Good (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Horace M. Towner (R) | William R. Green (R) | L. J. Dickinson (R) | William D. Boies (R) |
| 67th (1921–1923) | William F. Kopp (R) | Harry E. Hull (R) | Burton E. Sweet (R) | Gilbert N. Haugen (R) | Cyrenus Cole (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Horace M. Towner (R) | William R. Green (R) | L. J. Dickinson (R) | William D. Boies (R) |
| 68th (1923–1925) | William F. Kopp (R) | Harry E. Hull (R) | Thomas J. B. Robinson (R) | Gilbert N. Haugen (R) | Cyrenus Cole (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Horace M. Towner (R) | William R. Green (R) | L. J. Dickinson (R) | William D. Boies (R) |
| 68th (1923–1925) | William F. Kopp (R) | Harry E. Hull (R) | Thomas J. B. Robinson (R) | Gilbert N. Haugen (R) | Cyrenus Cole (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Hiram Evans (R) | William R. Green (R) | L. J. Dickinson (R) | William D. Boies (R) |
| 69th (1925–1927) | William F. Kopp (R) | F. Dickinson Letts (R) | Thomas J. B. Robinson (R) | Gilbert N. Haugen (R) | Cyrenus Cole (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Lloyd Thurston (R) | William R. Green (R) | L. J. Dickinson (R) | William D. Boies (R) |
| 70th (1927–1929) | William F. Kopp (R) | F. Dickinson Letts (R) | Thomas J. B. Robinson (R) | Gilbert N. Haugen (R) | Cyrenus Cole (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Lloyd Thurston (R) | William R. Green (R) | L. J. Dickinson (R) | William D. Boies (R) |
| 70th (1927–1929) | William F. Kopp (R) | F. Dickinson Letts (R) | Thomas J. B. Robinson (R) | Gilbert N. Haugen (R) | Cyrenus Cole (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Lloyd Thurston (R) | Earl Vincent (R) | L. J. Dickinson (R) | William D. Boies (R) |
| 71st (1929–1931) | William F. Kopp (R) | F. Dickinson Letts (R) | Thomas J. B. Robinson (R) | Gilbert N. Haugen (R) | Cyrenus Cole (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Lloyd Thurston (R) | Charles E. Swanson (R) | L. J. Dickinson (R) | Ed H. Campbell (R) |
| 72nd (1931–1933) | William F. Kopp (R) | Bernhard M. Jacobsen (D) | Thomas J. B. Robinson (R) | Gilbert N. Haugen (R) | Cyrenus Cole (R) | C. William Ramseyer (R) | Cassius C. Dowell (R) | Lloyd Thurston (R) | Charles E. Swanson (R) | Fred C. Gilchrist (R) | Ed H. Campbell (R) |

### 1933–1943: 9 seats

Following the 1930 census, Iowa was apportioned 9 seats.
| Congress | District | District | District | District | District | District | District | District | District |
| Congress | 1st | 2nd | 3rd | 4th | 5th | 6th | 7th | 8th | 9th |
| 73rd (1933–1935) | Edward C. Eicher (D) | Bernhard M. Jacobsen (D) | Albert Willford (D) | Fred Biermann (D) | Lloyd Thurston (R) | Cassius C. Dowell (R) | Otha Wearin (D) | Fred C. Gilchrist (R) | Guy Gillette (D) |
| 74th (1935–1937) | Edward C. Eicher (D) | Bernhard M. Jacobsen (D) | John W. Gwynne (R) | Fred Biermann (D) | Lloyd Thurston (R) | Hubert Utterback (D) | Otha Wearin (D) | Fred C. Gilchrist (R) | Guy Gillette (D) |
| 75th (1937–1939) | Edward C. Eicher (D) | William S. Jacobsen (D) | John W. Gwynne (R) | Fred Biermann (D) | Lloyd Thurston (R) | Cassius C. Dowell (R) | Otha Wearin (D) | Fred C. Gilchrist (R) | Vincent F. Harrington (D) |
| 76th (1939–1941) | Thomas E. Martin (R) | William S. Jacobsen (D) | John W. Gwynne (R) | Henry O. Talle (R) | Karl M. LeCompte (R) | Cassius C. Dowell (R) | Ben F. Jensen (R) | Fred C. Gilchrist (R) | Vincent F. Harrington (D) |
| 77th (1941–1943) | Thomas E. Martin (R) | William S. Jacobsen (D) | John W. Gwynne (R) | Henry O. Talle (R) | Karl M. LeCompte (R) | Paul Cunningham (R) | Ben F. Jensen (R) | Fred C. Gilchrist (R) | Vincent F. Harrington (D) |
| 77th (1941–1943) | Thomas E. Martin (R) | William S. Jacobsen (D) | John W. Gwynne (R) | Henry O. Talle (R) | Karl M. LeCompte (R) | Paul Cunningham (R) | Ben F. Jensen (R) | Fred C. Gilchrist (R) | Harry Narey (R) |

### 1943–1963: 8 seats

Following the 1940 census, Iowa was apportioned 8 seats.
| Congress | District | District | District | District | District | District | District | District |
| Congress | 1st | 2nd | 3rd | 4th | 5th | 6th | 7th | 8th |
| 78th (1943–1945) | Thomas E. Martin (R) | Henry O. Talle (R) | John W. Gwynne (R) | Karl M. LeCompte (R) | Paul Cunningham (R) | Fred C. Gilchrist (R) | Ben F. Jensen (R) | Charles B. Hoeven (R) |
| 79th (1945–1947) | Thomas E. Martin (R) | Henry O. Talle (R) | John W. Gwynne (R) | Karl M. LeCompte (R) | Paul Cunningham (R) | James I. Dolliver (R) | Ben F. Jensen (R) | Charles B. Hoeven (R) |
| 80th (1947–1949) | Thomas E. Martin (R) | Henry O. Talle (R) | John W. Gwynne (R) | Karl M. LeCompte (R) | Paul Cunningham (R) | James I. Dolliver (R) | Ben F. Jensen (R) | Charles B. Hoeven (R) |
| 81st (1949–1951) | Thomas E. Martin (R) | Henry O. Talle (R) | H. R. Gross (R) | Karl M. LeCompte (R) | Paul Cunningham (R) | James I. Dolliver (R) | Ben F. Jensen (R) | Charles B. Hoeven (R) |
| 82nd (1951–1953) | Thomas E. Martin (R) | Henry O. Talle (R) | H. R. Gross (R) | Karl M. LeCompte (R) | Paul Cunningham (R) | James I. Dolliver (R) | Ben F. Jensen (R) | Charles B. Hoeven (R) |
| 83rd (1953–1955) | Thomas E. Martin (R) | Henry O. Talle (R) | H. R. Gross (R) | Karl M. LeCompte (R) | Paul Cunningham (R) | James I. Dolliver (R) | Ben F. Jensen (R) | Charles B. Hoeven (R) |
| 84th (1955–1957) | Fred Schwengel (R) | Henry O. Talle (R) | H. R. Gross (R) | Karl M. LeCompte (R) | Paul Cunningham (R) | James I. Dolliver (R) | Ben F. Jensen (R) | Charles B. Hoeven (R) |
| 85th (1957–1959) | Fred Schwengel (R) | Henry O. Talle (R) | H. R. Gross (R) | Karl M. LeCompte (R) | Paul Cunningham (R) | Merwin Coad (D) | Ben F. Jensen (R) | Charles B. Hoeven (R) |
| 86th (1959–1961) | Fred Schwengel (R) | Leonard G. Wolf (D) | H. R. Gross (R) | Steven V. Carter (D) | Neal Smith (D) | Merwin Coad (D) | Ben F. Jensen (R) | Charles B. Hoeven (R) |
| 87th (1961–1963) | Fred Schwengel (R) | James E. Bromwell (R) | H. R. Gross (R) | John Henry Kyl (R) | Neal Smith (D) | Merwin Coad (D) | Ben F. Jensen (R) | Charles B. Hoeven (R) |

### 1963–1973: 7 seats

Following the 1960 census, Iowa was apportioned 7 seats.
| Congress | District | District | District | District | District | District | District |
| Congress | 1st | 2nd | 3rd | 4th | 5th | 6th | 7th |
| 88th (1963–1965) | Fred Schwengel (R) | James E. Bromwell (R) | H. R. Gross (R) | John Henry Kyl (R) | Neal Smith (D) | Charles B. Hoeven (R) | Ben F. Jensen (R) |
| 89th (1965–1967) | John R. Schmidhauser (D) | John Culver (D) | H. R. Gross (R) | Bert Bandstra (D) | Neal Smith (D) | Stanley L. Greigg (D) | John R. Hansen (D) |
| 90th (1967–1969) | Fred Schwengel (R) | John Culver (D) | H. R. Gross (R) | John Henry Kyl (R) | Neal Smith (D) | Wiley Mayne (R) | William J. Scherle (R) |
| 91st (1969–1971) | Fred Schwengel (R) | John Culver (D) | H. R. Gross (R) | John Henry Kyl (R) | Neal Smith (D) | Wiley Mayne (R) | William J. Scherle (R) |
| 92nd (1971–1973) | Fred Schwengel (R) | John Culver (D) | H. R. Gross (R) | John Henry Kyl (R) | Neal Smith (D) | Wiley Mayne (R) | William J. Scherle (R) |

### 1973–1993: 6 seats

Following the 1970 census, Iowa was apportioned 6 seats.
| Congress | 1st district | 2nd district | 3rd district | 4th district | 5th district | 6th district |
| 93rd (1973–1975) | Edward Mezvinsky (D) | John Culver (D) | H. R. Gross (R) | Neal Smith (D) | William Scherle (R) | Wiley Mayne (R) |
| 94th (1975–1977) | Edward Mezvinsky (D) | Mike Blouin (D) | Chuck Grassley (R) | Neal Smith (D) | Tom Harkin (D) | Berkley Bedell (D) |
| 95th (1977–1979) | Jim Leach (R) | Mike Blouin (D) | Chuck Grassley (R) | Neal Smith (D) | Tom Harkin (D) | Berkley Bedell (D) |
| 96th (1979–1981) | Jim Leach (R) | Tom Tauke (R) | Chuck Grassley (R) | Neal Smith (D) | Tom Harkin (D) | Berkley Bedell (D) |
| 97th (1981–1983) | Jim Leach (R) | Tom Tauke (R) | T. Cooper Evans (R) | Neal Smith (D) | Tom Harkin (D) | Berkley Bedell (D) |
| 98th (1983–1985) | Jim Leach (R) | Tom Tauke (R) | T. Cooper Evans (R) | Neal Smith (D) | Tom Harkin (D) | Berkley Bedell (D) |
| 99th (1985–1987) | Jim Leach (R) | Tom Tauke (R) | T. Cooper Evans (R) | Neal Smith (D) | Jim Ross Lightfoot (R) | Berkley Bedell (D) |
| 100th (1987–1989) | Jim Leach (R) | Tom Tauke (R) | Dave Nagle (D) | Neal Smith (D) | Jim Ross Lightfoot (R) | Fred Grandy (R) |
| 101st (1989–1991) | Jim Leach (R) | Tom Tauke (R) | Dave Nagle (D) | Neal Smith (D) | Jim Ross Lightfoot (R) | Fred Grandy (R) |
| 102nd (1991–1993) | Jim Leach (R) | Jim Nussle (R) | Dave Nagle (D) | Neal Smith (D) | Jim Ross Lightfoot (R) | Fred Grandy (R) |

### 1993–2013: 5 seats

Following the 1990 census, Iowa was apportioned 5 seats.
| Congress | 1st district | 2nd district | 3rd district | 4th district | 5th district |
| 103rd (1993–1995) | Jim Leach (R) | Jim Nussle (R) | Jim Ross Lightfoot (R) | Neal Smith (D) | Fred Grandy (R) |
| 104th (1995–1997) | Jim Leach (R) | Jim Nussle (R) | Jim Ross Lightfoot (R) | Greg Ganske (R) | Tom Latham (R) |
| 105th (1997–1999) | Jim Leach (R) | Jim Nussle (R) | Leonard Boswell (D) | Greg Ganske (R) | Tom Latham (R) |
| 106th (1999–2001) | Jim Leach (R) | Jim Nussle (R) | Leonard Boswell (D) | Greg Ganske (R) | Tom Latham (R) |
| 107th (2001–2003) | Jim Leach (R) | Jim Nussle (R) | Leonard Boswell (D) | Greg Ganske (R) | Tom Latham (R) |
| 108th (2003–2005) | Jim Nussle (R) | Jim Leach (R) | Leonard Boswell (D) | Tom Latham (R) | Steve King (R) |
| 109th (2005–2007) | Jim Nussle (R) | Jim Leach (R) | Leonard Boswell (D) | Tom Latham (R) | Steve King (R) |
| 110th (2007–2009) | Bruce Braley (D) | Dave Loebsack (D) | Leonard Boswell (D) | Tom Latham (R) | Steve King (R) |
| 111th (2009–2011) | Bruce Braley (D) | Dave Loebsack (D) | Leonard Boswell (D) | Tom Latham (R) | Steve King (R) |
| 112th (2011–2013) | Bruce Braley (D) | Dave Loebsack (D) | Leonard Boswell (D) | Tom Latham (R) | Steve King (R) |

### 2013–present: 4 seats

Following the 2010 census, Iowa was apportioned 4 seats.
| Congress | 1st district | 2nd district | 3rd district | 4th district |
| 113th (2013–2015) | Bruce Braley (D) | Dave Loebsack (D) | Tom Latham (R) | Steve King (R) |
| 114th (2015–2017) | Rod Blum (R) | Dave Loebsack (D) | David Young (R) | Steve King (R) |
| 115th (2017–2019) | Rod Blum (R) | Dave Loebsack (D) | David Young (R) | Steve King (R) |
| 116th (2019–2021) | Abby Finkenauer (D) | Dave Loebsack (D) | Cindy Axne (D) | Steve King (R) |
| 117th (2021–2023) | Ashley Hinson (R) | Mariannette Miller-Meeks (R) | Cindy Axne (D) | Randy Feenstra (R) |
| 118th (2023–2025) | Mariannette Miller-Meeks (R) | Ashley Hinson (R) | Zach Nunn (R) | Randy Feenstra (R) |
| 119th (2025–2027) | Mariannette Miller-Meeks (R) | Ashley Hinson (R) | Zach Nunn (R) | Randy Feenstra (R) |

## Key

* Democratic (D)
* Greenback (GB)
* Republican (R)
* Whig (W)