Month/Year History
July 1969 Founded as ELCO Co., Ltd. (Capital 2.5 million yen)
ELCO stood for "Electronics" and "Control" – our main business being the use of electronics to control devices.
February 1970 Opened Tokyo Sales Office (became a branch in February 1971)
July 1973 Built two-story steel-framed Head Office (total floor area 607 m2) in Kami-Akae Machi, Toyama City, Toyama Prefecture (area 3,487 m2)


August 1977 Opened Osaka Sales Office (became a branch in November 1986)
April 1978 Introduced QC Circle activities
Began with 16 circles.
June 1978 Began to specialize in power supply business.
July 1980 Acquired 5,502 m2 of land next door to Head Office, and began operations at three-story, steel-framed 2,723 m2 plant.


May 1982 Introduced TQC (Total Quality Control)
June 1983 Opened Nagoya Sales Office (became a branch in May 1992)
Introduced Policy Management (definition of Long-term Policy and Annual Policy)
July 1985 Opened Tama Sales Office
March 1988 Introduced Toyota Manufacturing Method
March 1989 Completed Tateyama Factory in Tateyama Machi, Toyama Prefecture


May 1990 Established U.S. ELCO., INC. (currently COSEL U.S.A., INC.) in San Jose, California, targeting Silicon Valley, where high-tech industry and venture companies are present in high concentrations.
September 1990 Opened Kyoto Sales Office
April 1992 Company name changed from ELCO Co., Ltd. to COSEL Co., Ltd.
  • Co-Organization (cooperation/teamwork)
  • System
  • Electronics
  • Liveliness
CO: Cooperation/Teamwork, S: Systems, E: Electronics, L: Liveliness The initials from these four concepts were taken to make the Company name. The Japanese verb "Cosu" means to go beyond, and so our company means to "Cosu," or go beyond, the original ELCO.
June 1993 Accredited under International Standard ISO 9001, relating to quality control and quality assurance (the first accreditation in Toyama Prefecture).
December 1994 Shares in the Company registered.
Additional financing brought capital to 2.055 billion yen.
May 1996 Introduced TMP.
May 1997 Extension offices in Saitama and Nagano changed to Sales Offices.
July 1997 Established COSEL EUROPE GmbH, a sales subsidiary in Germany.
May 1998 Established COSEL ASIA LTD., a sales subsidiary in Hong Kong.
January 1999 Shares listed on the Tokyo Stock Exchange and Nagoya Stock Exchange Market Division 2.
November 1999 Won TPM Excellence 1st Category.
December 1999 Acquired accreditation under International Standard ISO 14001, relating to environmental activities.
May 2000 Shares listed on the Tokyo Stock Exchange and Nagoya Stock Exchange Market Division 1.
May 2002 Head Office extended to a four-story, steel-framed building (total area 3,842.36 m2).


November 2002 Established COSEL Shanghai Electronics Co., Ltd., a sales subsidiary in Shanghai, China.
May 2004 Branches and Extension offices closed, and all sales locations unified into "Sales Offices."
December 2004 Opened Hamamatsu Sales Office.
December 2004 Group-wide Quality Control (GWQC) activities begin, to include partner companies.
March 2005 Began noise filter business.
December 2005 Won the QC Circle Ishikawa Kaoru Award for the first time.
February 2006 Completed compliance with RoHS instructions.
October 2006 Won the QC Circle Managers Award.
May 2007 Tateyama Factory extended to a two-story, steel-framed building (total area 5,259.68 m2).


February 2008 Won the Gold Award at the JHS All-Japan QC Circle Championships.
November 2011 Established SHANGHAI COSEL INTERNATIONAL TRADING CO., LTD., an export subsidiary in Shanghai, China.
December 2011 Established WUXI COSEL ELECTRONICS CO., LTD., a manufacturing subsidiary in Jiangsu Province, China.
June 2013 Kyoto and Kobe Sales Offices merged with Osaka Sales Office.
November 2013 Tachikawa and Atsugi Sales Offices merged with Kawasaki Sales Office.
December 2013 Kawasaki Sales Office changed name to Metropolitan Area Sales Office. Hamamatsu Sales Office moved and changed name to Shizuoka Sales Office.
August 2015 Completed incorporation of Vietnam Plant. Cosel Vietnam Co., Ltd., a transformer-manufacturing subsidiary.
July 2018 Acquired POWERBOX International AB.
August 2018 Built R&D Center(five-story steel-framed, total floor area 8,205.67㎡) in KamiAkae Machi, Toyama City.
October 2018 Began operations at R&D Center.
June 2022 Opened Kyoto Sales Office.