Saran District is one of the thirty-eight districts of Bihar state, India. The district, part of Saran Division, is also known as Chhapra district after the headquarters of the district, Chhapra.

Hathwa Raj was a zamindar in the Saran Division of Bihar belonging to Bhumihar Brahmins, which encompassed 1,365 villages, was inhabited by more than 391,000 people, and produced an annual rental of almost a million rupees.

Saran district occupies an area of 2,641 square kilometres (1,020 sq mi),[ equivalent to Drenthe province in the Netherlands.

It is one of the 38 districts in Bihar currently receiving funds from the Backward Regions Grant Fund Programme (BRGF).

According to the 2011 census Saran district has a population of 3,943,098, roughly equal to the nation of Liberia or the US state of Oregon.This gives it a ranking of 60th in India (out of a total of 640).The district has a population density of 1,493 inhabitants per square kilometre (3,870/sq mi).Its population growth rate over the decade 2001-2011 was 21.37%.Saran has a sex ratio of 949 females for every 1000 males, and a literacy rate of 68.57%.