Cleaners found 24 gold bars worth around €834,000 hidden in an airliner toilet after a flight from Bangkok landed in India.
The Jet Airways plane was being cleaned in Calcutta before a scheduled flight to Patna when the bars were discovered inside two bags.
A customs spokesman said the bars weighed around 1 kilogram each.
They confiscated the stash and are investigating.
India is one of the world’s biggest consumers of gold.
The government increased the gold import duty recently which has encouraged smuggling.