Insurance Regulatory and Development Authority of India (IRDAI) is an autonomous apex statutory body which regulates and develops the insurance industry in India. It was constituted by a Parliament of India act called Insurance Regulatory and Development Authority Act, 1999
As you asking for the contact details of the IRDA Delhi office the contact details of the IRDA Delhi office is given below :
Insurance Regulatory and Development Authority of India

Delhi Office – Gate No. 3
Jeevan Tara Building, First Floor
Sansad Marg, New Delhi-110001
Ph: (011) - 2344 4400
Fax: (011) - 2374 7650
for your Future References here I am giving you the contact details of the IRDA other Head offices :

Head Office :

Insurance Regulatory and Development Authority of India
3rd Floor, Parisrama Bhavan, Basheer Bagh HYDERABAD 500 004
Telangana State (INDIA )

Ph: (040) 23381100
Fax: (040) 6682 3334

Mumbai Office:

Insurance Regulatory and Development Authority of India
Mumbai Regional Office
Royal Insurance Building
12, J. Tata Road, Ground Floor
Mumbai 400 020.
Near Churchgate)
Phone No.: 022- 22898600