New Delhi ( , Hindi: [ˈnəiː ˈdɪlːiː], ISO: Naī Dillī) is the capital of India and a part of the National Capital Territory of Delhi (NCT). New Delhi is the seat of all three branches of the Government of India, hosting the Rashtrapati Bhavan, Sansad Bhavan, and the Supreme Court. New Delhi is a municipality within the NCT, administered by the NDMC, which covers mostly Lutyens' Delhi and a few adjacent areas. The municipal area is part of a larger administrative district, the New Delhi district.

Although colloquially Delhi and New Delhi are used interchangeably to refer to the National Capital Territory of Delhi, both are distinct entities, with the municipality and the New Delhi district forming a relatively small part within the megacity of Delhi. The National Capital Region is an even larger entity, comprising the entire NCT along with adjoining districts in the two neighbouring states forming a continuously built-up area with it, including Ghaziabad, Noida, Greater Noida, Meerut, YEIDA City, Gurgaon, and Faridabad.

The foundation stone of New Delhi, south of central Delhi, was laid by George V during the Delhi Durbar of 1911. It was designed by British architects Edwin Lutyens and Herbert Baker. The new capital was inaugurated on 13 February 1931, by Viceroy and Governor-General Irwin.