February 1, 2016
Third term Republican Reid Ribble (WI-08) announced his retirement over the weekend, turning a safe Republican district into a toss-up race for 2016.
37 House members have announced they are not running this year, 22 Republicans and 15 Democrats. Of those, eight Republican seats are highly competitive (toss-up or lean per Sabato's Crystal Ball). Four are competitive on the Democratic side.
Seven members of each party are leaving to run for the U.S. Senate; a single Democrat is running for governor with another running for local office. The remaining six Democrats and 15 Republicans are retiring (or have not announced plans to run for another public office).
The full list of departures, as of February 1, follows: