Chennai-bound flights are 23.9% cheaper when booked a month ahead than a day before departure, while Ahmedabad flyers face a 60.6% fare gap and Bengaluru sees just 5%

Across seven routes into Chennai, booking a flight 30 days before departure cost 23.9 per cent less than booking the day before, according to fares captured on the morning of 28 October 2026. That compares with a saving of 13.7 per cent across the broader network, making Chennai 10.2 percentage points better than the national figure. All seven routes into the city were cheaper at 30 days than at the day-before mark.The chart shows the fare-time index by booking horizon for Chennai routes against the network.What does the fare-time index mean?The TOI-DPA Airline Price Index sets each route's day-before fare at 100 and expresses every other booking time as a number against it. A reading below 100 means fares at that booking horizon were lower than the day-before fare on the same route. A reading above 100 means they were higher. The index is built over a longer window than a single morning, so it reflects a pattern across multiple departure dates, not just one snapshot.For Chennai, the index stood at 78.7 at 90 days before departure, fell to 74.8 at 60 days, edged up to 76.1 at 30 days, climbed to 87.0 at 7 days, and reached 100.0 the day before. For the network, the corresponding readings were 88.1, 85.8, 86.3, 90.5, and 100.0. The lowest point on the Chennai curve was at 60 days, making that the cheapest booking horizon across the seven routes.Which route punishes late booking most?The route where waiting hurts most is Ahmedabad to Chennai. Its index at 30 days was 62.3, meaning someone who booked the day before paid 60.6 per cent more than someone who booked 30 days out. Ahmedabad to Chennai has approximately 3 flights per day into Chennai, making it a thinner route than most others in this group.At the other end, Bengaluru to Chennai showed the smallest penalty for late booking. Its 30-day index was 95.3, and the extra cost for booking the day before was 5.0 per cent. With approximately 14 flights per day, it is the most frequent route among the seven, and the fare gap between booking horizons is narrow by comparison.How the seven routes compareRouteFlights per day (approx)Ahmedabad to Chennai3Pune to Chennai2Kolkata to Chennai7Hyderabad to Chennai9Mumbai to Chennai12Delhi to Chennai13Bengaluru to Chennai14Flight counts move between captures, so these figures should be read as approximate.What should a traveller consider?The index points to 60 days before departure as the lowest-cost booking horizon across the seven Chennai routes, with the 30-day mark also well below the day-before fare. On the Ahmedabad to Chennai route, the difference between booking 30 days ahead and booking the day before was 60.6 per cent, a gap large enough to be worth planning around. On Bengaluru to Chennai, the same gap was only 5.0 per cent, so the timing of a booking matters far less on that corridor. These are patterns in advertised fares, not guarantees; any single quote can move.About this dataThese are advertised fares and medians across routes, not what any passenger finally paid, and a quote visible on one morning can move. All fares were captured on the morning of 28 October 2026. The data does not record which airline charged a fare, so it cannot say who sets these prices. Fare data was not available in this capture for Mumbai to Pune and Pune to Mumbai. The percentages come from the tracker's fare-time index, which is built over a longer window than a single morning. This compares what different departure dates cost when quoted at different booking times, not what one flight cost as its date approached. Flight counts move between captures, so how busy a route is should be read as approximate.The Chennai booking curve sits consistently below the national network curve at every horizon from 90 days to 7 days before departure, and the 10.2-percentage-point advantage at the 30-day mark is driven in large part by routes with fewer daily flights, where the spread between early and late fares is widest. On the busiest corridors into the city, that spread narrows sharply, so the benefit of early booking is not uniform across all seven routes.TOI-DPA Airline Price Index is a joint initiative of The Times of India and Decimal Point Analytics.Source: Decimal Point Analytics Airline Price IndexStay updated with the latest Flight Price Tracker news. Download the TOI App.