List of districts of the House of Councillors of Japan

The House of Councillors, the upper house of the Japanese National Diet is made up of 248 members elected from 45 districts plus a national proportional representation list. Until 2015, there were 47 districts which coincided with the 47 prefectures of Japan.

In order to address the imbalance in voter representation between rural and urban voters, the Public Officers Election Law was amended in 2012 and again in 2015. The 2015 amendment merged the two smallest districts, the Tottori and Shimane districts, to create a combined Tottori-Shimane at-large district, and merged the third- and fourth-smallest districts, the Kochi and Tokushima districts, to create a combined Tokushima-Kōchi at-large district. Other changes to the number of Councilors have also been made to address the imbalance.^[1] Below is a table of districts, sortable by name, magnitude and voter disparity, based on the official number of registered voters as of September 2015.