IndiGo passengers will have to pay for web check-in in line with a policy that came into effect on November 14, the airline said in a series of tweets on Sunday.
Passengers who opt for the free check-in at the airport counter cannot be guaranteed seats together even if they are booked on the same PNR and the group includes a child, the airline said in response to queries from tweeters.
The minimum charge for web check-in is Rs 100, for the middle seat in the last row, and the maximum is Rs 800, for a seat in the first row.
The decision came under fire, with several tweeters asking why the airline was not being transparent and raising fares instead.