List of districts of the House of Councillors of Japan explained

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.

List of districts

District	Registered voters^[2]	Magnitude	Disparity
			Pre-reform	Post-reform
Aichi	5,927,668	8
Akita	888,496	2
Aomori	1,122,948	2
Chiba	5,092,741	6
Ehime	1,169,427	2
Fukui	644,447	2
Fukuoka	4,135,977	6
Fukushima	1,607,908	2
Gifu	1,666,610	2
Gunma	1,616,400	2
Hiroshima	2,313,131	4
Hokkaido	4,537,448	6
Hyogo	4,536,912	6
Ibaraki	2,411,307	4
Ishikawa	939,531	2
Iwate	1,074,018	2
Kagawa	818,470	2
Kagoshima	1,371,073	2
Kanagawa	7,421,431	8
Kumamoto	1,473,659	2
Kyoto	2,088,383	4
Mie	1,489,396	2
Miyagi	1,907,518	2
Miyazaki	918,533	2
Nagano	1,737,214	2
Nagasaki	1,148,570	2
Nara	1,140,129	2
Niigata	1,925,565	2
Ōita	972,380	2
Okayama	1,566,428	2
Okinawa	1,115,392	2
Osaka	7,140,578	8
Saga	679,289	2
Saitama	5,933,788	8
Shiga	1,121,066	2
Shizuoka	3,052,579	4
Tochigi	1,621,930	2
Tokushima-Kochi	1,261,100	2
Tokyo	10,947,527	12
Tottori-Shimane	1,051,880	2
Toyama	888,832	2
Wakayama	825,373	2
Yamagata	937,920	2
Yamaguchi	1,173,848	2
Yamanashi	692,001	2
Total	104,106,821	148

National PR block

See main article: Japanese House of Councillors national proportional representation block. In addition to the smaller districts mentioned above, the House of Councillors also has a single block for the entire nation. It elects 50 members per election (100 in total) based on the D'Hondt method.

See also

• List of districts of the House of Representatives of Japan

Notes and References

1. Web site: Weighing Vote Disparity in Japan’s Upper House . 30 July 2015 . 29 February 2016.
2. As of 2 September 2015. Web site: 平成２７年９月２日現在選挙人名簿及び在外選挙人名簿登録者数 . Number of resident and non-resident enrolled voters as of 2 September 2015 . Japanese . 2 September 2015 . 29 February 2016.