A congressional district is an electoral constituency which elects a member of a congress. Countries that have congressional districts are Japan, the Philippines, and the United States. The size of a district is based on the number of people who live in that district. A district is often very big if there are few people that live there; a district is often small if it's in a big city because there would are many people living there.
| No. | District | Area in km² | Member(s) (from 2021) |
| 1 | Alaska At-large | 1.481.354 | Don Young (R) |
| 2 | Montana At-large | 376.981 | Matt Rosendale (R) |
| 3 | Wyoming At-large | 251.491 | Liz Cheney (R) |
| 4 | South Dakota At-large | 196.542 | Dusty Johnson (R) |
| 5 | New Mexico-2 | 185.806 | Yvette Herrell (R) |
| 6 | Oregon-2 | 179.857 | Cliff Bentz (R) |
| 7 | North Dakota At-large | 178.648 | Kelly Armstrong (R) |
| 8 | Nebraska-3 | 174.658 | Adrian M. Smith (R) |
| 9 | Texas-23 | 150.374 | Tony Gonzales(R) |
| 10 | Nevada-2 | 144.600 | Mark Amodei (R) |
| 11 | Arizona-1 | 142.553 | Tom O'Halleran (D) |
| 12 | Kansas-1 | 136.086 | Tracey Mann (R) |
| 13 | Nevada-4 | 132.085 | Steven Horsford (D) |
| 14 | Colorado-2 | 128.806 | Joe Neguse (D) |
| 15 | New Mexico-3 | 116.443 | Teresa Leger Fernandez (D) |
| 16 | Idaho-2 | 111.954 | Mike Simpson (R) |
| 17 | Utah-2 | 103.569 | Chris Stewart (R) |
| 18 | Idaho-1 | 102.093 | Russ Fulcher (R) |
| 19 | Texas-13 | 99.325 | Ronny Jackson (R) |
| 20 | Colorado-4 | 98.687 | Ken Buck (R) |
| No. | District | Area in km² | Member(s) (as of 2019) |
| 1 | New York-13 | 27 | Adriano Espaillat (D) |
| 2 | New York-10 | 37 | Jerrold Nadler (D) |
| 3 | New York-15 | 38 | José Serrano (D) |
| 4 | New York-12 | 39 | Carolyn B. Maloney (D) |
| 5 | New York-9 | 41 | Yvette Clarke (D) |
| 6 | New York-7 | 42 | Nydia Velázquez (D) |
| 7 | New York-14 | 74 | Alexandria Ocasio-Cortez (D) |
| 8 | New York-8 | 77 | Hakeem Jeffries (D) |
| 9 | New York-6 | 78 | Grace Meng (D) |
| 10 | California-12 | 101 | Nancy Pelosi (D) |
| 11 | California-34 | 124 | Jimmy Gomez (D) |
| 12 | New York-5 | 135 | Gregory Meeks (D) |
| 13 | Illinois-4 | 136 | Jesús García (D) |
| 14 | New Jersey-8 | 142 | Albio Sires (D) |
| 15 | California-37 | 144 | Karen Bass (D) |
| 16 | California-40 | 150 | Lucille Roybal-Allard (D) |
| - – | District of Columbia At-large | 160 | Eleanor Holmes Norton (D) |
| 17 | Illinois-7 | 162 | Danny K. Davis (D) |
| 18 | Massachusetts-7 | 163 | Ayanna Pressley (D) |
| 19 | New York-11 | 171 | Max Rose (D) |
| 20 | California-46 | 186 | Lou Correa (D) |
According to the 2020 Census, Texas will gain two additional House seats and will have 38 House seats in the future. Further, Colorado (8 in the future), Florida (28), Montana (2), North Carolina (14), and Oregon (6) will each gain an additional constituency. The following seven states will lose a constituency after the 2022 Midterm Elections: Illinois (17 in the future), California (52), Michigan (13), Ohio (15), New York (26), Pennsylvania (17), and West Virginia (2).
| Number of congressional election districts by state | |||
| State | Census 2000 | Census 2010 | Census 2020 |
| 7 | 7 | 7 | |
| 1 | 1 | 1 | |
| 8 | 9 | 9 | |
| 4 | 4 | 4 | |
| 7 | 7 | 8 | |
| 5 | 5 | 5 | |
| 1 | 1 | 1 | |
| 25 | 27 | 28 | |
| 13 | 14 | 14 | |
| 2 | 2 | 2 | |
| 2 | 2 | 2 | |
| 19 | 18 | 17 | |
| 9 | 9 | 9 | |
| 5 | 4 | 4 | |
| 53 | 53 | 52 | |
| 4 | 4 | 4 | |
| 6 | 6 | 6 | |
| 7 | 6 | 6 | |
| 2 | 2 | 2 | |
| 8 | 8 | 8 | |
| 10 | 9 | 9 | |
| 15 | 14 | 13 | |
| 8 | 8 | 8 | |
| 4 | 4 | 4 | |
| 9 | 8 | 8 | |
| 1 | 1 | ||
| 3 | 3 | 3 | |
| 3 | 4 | 4 | |
| 2 | 2 | 2 | |
| 13 | 12 | 12 | |
| New Mexico | 3 | 3 | 3 |
| 29 | 27 | 26 | |
| 13 | 13 | 14 | |
| 1 | 1 | 1 | |
| 18 | 16 | 15 | |
| 5 | 5 | 5 | |
| 5 | 5 | 6 | |
| 19 | 18 | 17 | |
| 2 | 2 | 2 | |
| 6 | 7 | 7 | |
| 1 | 1 | 1 | |
| 9 | 9 | 9 | |
| 32 | 36 | 38 | |
| 3 | 4 | 4 | |
| 1 | 1 | 1 | |
| 11 | 11 | 11 | |
| 9 | 10 | 10 | |
| 3 | 3 | 2 | |
| 8 | 8 | 8 | |
| 1 | 1 | 1 | |
| Total | 435 | 435 | 435 |
