After graduating in 1966, Sat Pal Khattar entered the civil service as a deputy public prosecutor and state counsel in the Attorney-General’s Chamber. Later that year, he joined the Inland Revenue Department as a legal officer and rose to become a senior legal officer in 1971. Khattar left the civil service in 1974 and set up his own law firm, which is currently one of the largest law firms in Singapore. After retirement, he remained chairman of his private investment firm, Khattar Holdings. In addition to that, he has held chairmanship and directorship of a number of organizations. He was formerly chairman of GuocoLand Ltd and director of Gateway Distriparks Ltd, India.

He is presently a life trustee of SINDA, a non-profit set up to foster and help the less fortunate members of the Indian community in Singapore. He is also vice-president of the Singapore Indian Education Trust, chairman of the International Management Action Awards Council, and director of the Lee Kuan Yew Exchange Fellowship.

In 2011 he was awarded the Padma Shri award. For his contributions to the civil service, he was awarded the Public Administrative Medal (Silver) at the National Day Awards in 1972.