As of December 2020, the Navy's sub-surface fleet includes one nuclear-powered attack submarine, one ballistic missile submarine, 15 conventionally-powered attack submarines. The conventional attack submarines of the Indian Navy consist of the Kalvari (French Scorpène-class submarine design), the Sindhughosh (Russian Kilo-class submarine design) and the Shishumar (German Type 209/1500 design) classes.
India also possesses a single Akula-class nuclear-powered attack submarine named INS Chakra. She is under lease to India for a period of ten years. Three hundred Indian Navy personnel were trained in Russia for the operation of these submarines. Negotiations are on with Russia for the lease of the second Akula-class submarine.
INS Arihant was launched on 26 July 2009 in Visakhapatnam, and was secretly commissioned into active service in August 2016. The Navy plans to have six nuclear-powered ballistic missile submarines in service in the near future. Arihant is both the first boat of the Arihant-class nuclear-powered ballistic missile submarines and the first nuclear-powered submarine to be built in India.