The Patiala and East Punjab States Union (PEPSU) was a former state of India. It was created out of the merger of several Punjabi princely states on July 15, 1948, formally becoming a state of India in 1950. The princely states that became part of PEPSU were Patiala, Nabha, Jind, Faridkot, Malerkotla, Kapurthala, and Kalsia. Most had Sikh rulers, and a majority of the population of the state was also Sikh. Most of the state was Punjabi-speaking, with some districts speaking Hindi. The state had an area of approximately 10,000 square miles (26,000 km²), and a population of 34,24,060 in 1948. PEPSU was roughly triangular, with Faridkot in the northwest corner, Jind in the southeast corner, and Rajpura in the northeast corner of the state. It was almost entirely surrounded by the state of Punjab, and had a northwestern exclave that included Kapurthala, a northeastern exclave in the Himalaya foothills around Kalka, and a southeastern exclave that included Narnaul on the border of Rajasthan. The capital and principal city was Patiala, and the last Maharaja of Patiala, Yadvindra Singh, served as Rajpramukh of the state during its short existence. The rajpramukh was appointed by the President of India, but the residents of the state also elected a 60-member state assembly, first elected on January 6, 1952. The Congress Party won 26 seats and Akali Dal 19 seats.

On November 1, 1956, PEPSU was merged into Punjab state. Part of the former state of PEPSU, including the southeastern portion of the state around Jind and the Narnaul exclave, presently lie within the state of Haryana, which was separated from Punjab in 1966.