You need to apply for a Transit Visa if you are going to change from the International Terminal to the Domestic Terminal of any Indian Airport or if you are going to stay in an airport hotel even for a few hours. In case you remain within limits of the waiting area reserved for International Transit Passengers of the Indian Airport and are not going to cross Immigration Controls at any time, you do not need a transit visa.
Please note: the maximum period of stay in India permitted for a Transit Visa is 72 hours/3 days for each entry and is issued only when Transit/Travel is by Air. The Transit Visa is valid for 15 days only.
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