The RBI intervened more in soaking up dollars rather than in selling the greenback to prevent the rupee from rising sharply on robust forex inflows in September.
The central bank had bought a total $9.04 billion and sold $4.39 billion of spot forex when the rupee moved in the 66.3250-67.1450 range, with inflows amounting to $2.9 billion, the second-highest in a month so far this year.
After September, the flows reversed, with India like other emerging markets witnessing heavy outflows every month.
The RBI also net sold $220 million in September in currency futures market, while its forwards dollar purchases stood at $4.89 billion, it said.