A short time after joining the business, Ispahani was made a junior partner. When his father died in May 1925, he became the senior partner of the firm along with two other partners, his brothers,
Mirza Abol Hassan Ispahani and Mirza Mahmood Ispahani. In 1934,
M. M. Ispahani and partnership was converted to a limited liability company in
Kolkata.
Orient Airways was founded by Mirza Ahmad Ispahani and
Adamjee Haji Dawood on 23 October 1946. In 1948 the company was moved to
Chittagong,
East Pakistan. On 11 March 1955 Orient Airways was merged with a proposed airline of the Pakistan Government and turned into
Pakistan International Airlines Corporation, the national airline of Pakistan. After the
Bangladesh Liberation War, his properties were nationalized under the
Enemy Property Act. Ahmad Ispahani personally went to meet
Sheikh Mujibur Rahman and requested that his properties be denationalized. Mujib had the law specially changed for Ahmad Ispahani and handed all his properties back to him. When
Ziaur Rahman became the president, he requested that Ahmad Ispahani become the chairman of
Biman, because of his expertise in the aviation industry. However, he politely turned down the offer. == Legacy ==