Tokyo Tekko Co., Ltd. (TTK) is founded in Adachi-ku, Tokyo, to produce pig iron and cast iron.

Production of ordinary steel ingots starts.

The Oyama Factory Steel-Making Mill (currently Oyama Works) is established in Oyama City, Tochigi Prefecture.

The Oyama Factory Rolling Mill is established to start the production of steel bars.

TTK acquires a controlling interest in Musashi Steelworks (currently Tokyo Tekko Doboku Co., Ltd., a consolidated subsidiary).

TTK is listed on the Second Section of the Tokyo Stock Exchange.

Totetsu Koun Co., Ltd. (currently a consolidated subsidiary) is founded in Adachi-ku, Tokyo.

TTK is listed on the First Section of the Tokyo Stock Exchange.

The Hachinohe Works Steel-Making Mill is established in Hachinohe City, Aomori Prefecture.

The Head Office is relocated to 520 Yokokura Shinden, Oyama City, Tochigi Prefecture. The Oyama Factory is renamed Oyama Works as TTK’s main factory.

The Sakai Office is established in Sakai Town, Sashima District, Ibaraki Prefecture, to produce pig iron and cast iron products.

Totetsu Sangyo Co., Ltd. (currently a consolidated subsidiary) is founded in Oyama City, Tochigi Prefecture.

TTK enters into a business partnership with Godo Steel, Ltd.

The Hachinohe Works Rolling Mill is established to start the production of steel bars.

The Building Center of Japan approves TTK's joining method for high-tensile threaded rebars (Neji-Tetsu-Con) (Evaluation No. BCJ−C1039).

Totetsu Kenzai K.K. is founded in Hachinohe City, Aomori Prefecture.

Totetsu Maintenance K.K. (currently a consolidated subsidiary) is founded in Oyama City, Tochigi Prefecture.

TTK receives a general construction business license: License from the Governor of Tochigi Prefecture (General-1) No. 16576.

TTK acquires a controlling interest in Shintou Co., Ltd.

The Cut & Bend Center is established in Oyama City, Tochigi Prefecture.

Kanto Metal Co., Ltd. (currently a consolidated subsidiary) is founded in Sakai Town, Sashima District, Ibaraki Prefecture.

Oyama Works and Hachinohe Works acquire ISO quality management system certification ISO 9002/JIS Z 9902.

The Head Office of Totetsu Koun Co., Ltd. is relocated to Oyama City.

The Tokyo Head Office is relocated to Shinjuku-ku, Tokyo.

Tohoku Environmental Clean System Co., Ltd. is founded in Hachinohe City, Aomori Prefecture.

Tohoku Tokyo Tekko Co., Ltd. is founded in Hachinohe City, Aomori Prefecture, to take over the operations of the Hachinohe Works.

TTK jointly establishes Tokyo D-bar Steel Co., Ltd. with Godo Steel, Ltd. (opened for business in April 2002).

TTK acquires full ownership of YOSHIEI, a private limited company.

Tohoku Tokyo Tekko Co., Ltd. acquires ISO environmental management system certification ISO 14001/JIS Q 14001.

Tohoku Tokyo Tekko Co., Ltd. jointly establishes Tohoku D-bar Steel Co., Ltd. with Itoh Iron & Steel Co., Ltd. (opened for business in April 2005).

Tokyo Tekko Co., Ltd. acquires ISO environmental management system certification ISO 14001/JIS Q 14001.

Tohoku Tokyo Tekko Co., Ltd. and Shintou Co., Ltd. merge (keeping the name Tohoku Tokyo Tekko Co., Ltd.).

TTK absorbs YOSHIEI.

The Tokyo Head Office is relocated to Chiyoda-ku, Tokyo.

Tohoku Environmental Clean System Co., Ltd. is liquidated.

Tokyo  D-bar Steel Co., Ltd. is liquidated.

TTK KOREA CO., LTD. (currently a consolidated subsidiary) is founded in Seoul City, South Korea.

Totetsu Kenzai K.K. is liquidated.

Totetsu Shigen K.K. (currently a consolidated subsidiary) is founded in Hachinohe City, Aomori Prefecture.

TTK absorbs Tohoku Tokyo Tekko Co., Ltd.

TTK establishes capital business partnership with ITO Iron & Steel Co.Ltd and registers it as the equity method affiliate.

TTK jointly establishes Tokyo D-bar Sales Co.Ltd with ITO Iron & Steel Co.Ltd. (opened for business in Feb.2019)