In every election cycle a certain number of representatives retire leaving behind open seats for their parties to defend. In 2018, the number of open seats, especially Republican held seats, is unusually large. Here are the number of retirements in recent years:

Year Democrats Republicans 2016 18 25 2014 17 25 2012 22 19 2010 17 20 2008 6 27 2006 9 18

This year 19 Democrats and 38 Republicans are retiring at the end of their current term.

Here are the announced retirements so far, sorted on PVI (Partisan Voting Index).

Any seat between R+5 and D+5 is a swing district that has to be fought over, even more so

if occupied by the other party. Pennsylvania districts are not included since the courts redrew the entire map this year.

Representative Party District PVI Reason for leaving Diane Black Republican TN-06 R+24 Ran for governor and lost primary Marsha Blackburn Republican TN-07 R+20 Running for senator Evan Jenkins Republican WV-03 R+23 Running for senator Raul Labrador Republican ID-01 R+21 Running for governor Diane Black Republican TN-06 R+20 Running for governor John Duncan Jr. Republican TN-02 R+20 Retiring from public office Luke Messer Republican IN-06 R+18 Running for senator Todd Rokita Republican IN-04 R+17 Running for senator Jim Bridenstine Republican OK-01 R+17 Was appointed NASA administrator Kevin Cramer Republican ND-AL R+16 Running for senator Jeb Hensarling Republican TX-05 R+16 Retiring from public office Harold "Trey" Gowdy III Republican SC-04 R+5 Retiring from public office Kristi Noem Republican SD-AL R+14 Running for governor Bob Goodlatte Republican VA-06 R+13 Retiring from public office Gregg Harper Republican MS-03 R+13 Retiring from public office Sam Johnson Republican TX-03 R+13 Retiring from public office Tom Rooney Republican FL-17 R+13 Retiring from public office Ted Poe Republican TX-02 R+11 Retiring from public office Chris Collins Republican NY-27 R+11 Arrested for insider trading Lynn Jenkins Republican KS-02 R+10 Retiring from public office Lamar Smith Republican TX-21 R+10 Retiring from public office Mark Sanford Republican SC-01 R+10 Lost renomination Joe Barton Republican TX-06 R+9 Got caught sending out dirty pictures James Renacci Republican OH-16 R+8 Running for governor Robert Pittenger Republican NC-09 R+7 Lost renomination Ron DeSantis Republican FL-06 R+7 Running for governor Steve Pearce Republican NM-02 R+6 Running for governor Dennis Ross Republican FL-15 R+6 Retiring from public office Tom Garrett Republican VA-05 R+6 White nationalism, alcohol problem Paul Ryan Republican WI-01 R+5 Couldn't take the heat any more Tim Walz Democratic MN-01 R+5 Running for governor Dave Trott Republican MI-11 R+4 Retiring from public office Rick Nolan Democratic MN-08 R+4 Retiring from public office Rodney Frelinghuysen Republican NJ-11 R+3 Retiring from public office Carol Shea-Porter Democratic NH-01 R+2 Retiring from public office Jacky Rosen Democratic NV-03 R+2 Running for senator Darrell Issa Republican CA-49 R+1 Retiring from public office Frank LoBiondo Republican NJ-02 R+1 Retiring from public office Martha McSally Republican AZ-02 R+1 Running for senator Dave Reichert Republican WA-08 Even Retiring from public office Ed Royce Republican CA-39 Even Retiring from public office Elizabeth Esty Democratic CT-05 D+2 She failed to fire abusive staffer Ruben Kihuen Democratic NV-04 D+3 Sex scandal Sander Levin Democratic MI-09 D+4 Has a position at the University of Michigan Kyrsten Sinema Democratic AZ-09 D+4 Running for senator Ileana Ros-Lehtinen Republican FL-27 D+5 Retiring from public office John Delaney Democratic MD-06 D+6 Running for president Michelle Lujan-Grisham Democratic NM-01 D+7 Running for governor Louise Slaughter Democratic NY-25 D+8 Louise Slaughter died Niki Tsongas Democratic MA-03 D+9 Retiring from public office Jared Polis Democratic CO-02 D+9 Running for governor Colleen Hanabusa Democratic HI-01 D+17 Running for governor Beto O'Rourke Democratic TX-16 D+17 Running for senator Gene Green Democratic TX-29 D+19 Retiring from public office Keith Ellison Democratic MN-05 D+26 Running for attorney general John Conyers Democratic MI-13 D+32 Sex scandal Luis Gutierrez Democratic IL-04 D+33 Retiring from public office

In addition, there are seven vacancies in the House. All require special elections. However, some of these will be held on election day (MI-13, PA-07, and PA-15), which is effectively the same as an open seat, since no incumbent will be running. For this reason, we have counted these as retirements, rather than resignations.

Furthermore, special elections will be held in OH-12 on Aug. 7, TX-27 on June 30, and in OK-01 and NY-25 on dates to be determined.