As of 1 April 2016, which one of the following states had the largest coal reserves in India?

Jharkhand had the largest total geological coal resources in the official inventory of 1 April 2016. This concerns the combined geological resource categories, not annual coal production or only the proved category.

Current law: The Ministry of Coal annual report 2025–26 records Odisha first in the inventory of 1 April 2025, with 100,975.78 million tonnes, ahead of Jharkhand at 93,254.06 million tonnes. The answer above is therefore tied to the 1 April 2016 inventory and does not hold for that later inventory.