What the Airlines Actually Allow
IndiGo does not allow pets in the cabin. Air India does, but only on select routes and only for cats and dogs under 7 kg combined weight with the carrier. Akasa Air permits in-cabin pets on domestic sectors with advance notice. Vistara, now merged into Air India, had the most straightforward in-cabin policy while it operated, that framework is now absorbed into Air India's rules, so verify directly before booking.