1966

• Iran Transfo Co. was established in 1966 under license of SIEMENS (Germany) as a transformer manufacturer including oil-immersed distribution, medium and large power transformers.
• Construction of the transformer plant in Rey, Tehran for designing and manufacturing oil-immersed distribution transformers.

1976

• Construction of the transformer plant was started in Zanjan for designing and manufacturing oil-immersed distribution, medium and large power transformers.

2000

• Iran Transfo has developed into a corporation consisting of 4 transformer manufacturing factories (Iran Transfo Co, Iran Transfo Rey Co, Zangan Distribution Transformer Co and Kooshkan Transformers Co) and 10 Other subsidiary companies.
• Foundation of Zanjan Sadaf Gostar Insulator Co for manufacturing porcelain bushings and insulators.
• Foundation of Zanjan Saba Insurance Services Company for providing all types of insurance services.
• Foundation of Iran Transformer Research Institute
• Foundation of Trans Post Pars Co, As an EPC contractor for H.V substations up to 400Kv.
• Foundation of KOOSHKAN TRANSFORMERS CO,As a member of Iran Transfo Corporation for design and manufacturing three phase oil-immersed distributiontransformers up to 4000 KVA, 36 Kv.
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• Foundation of Iran Transfo Substations Development Company for designing and manufacturing of prefabricated distribution substations.
• Foundation of Ashna Rahe Sama as a transportation company.

• Designing and manufacturing of first Cast Resin Dry-type Transformer in class F.
• Foundation of Iran Transfo Commercial Company for providing integrated sales and procurement services.
• Foundation of Pars Electrical Insulations Co, as a member for manufacturing insulation materials.
• Foundation of Iran Transfo After Sales Services Co (ITASS), in order to provide all related services to transformers and their accessories .

• Foundation of Zangan Industrial Oil Refining Co, for manufacturing transformer and industrial oils and industrial oil and solvents.

2016

         Opening a new transformer plant in Parand industrial zone (south of Tehran) in an area of about 132000 Square meters.