Thanks to vigorous competition, domestic flights in India are currently the cheapest in the world according to a survey by GoEuro, a Berlin-based travel search website published this month.

The survey  found that it costs $10.36, or Rs 626.90, on average, to travel 100 kilometres on a commercial flight in India. That is about half the cost of flying in China and cheaper than the average price of $14.89 or Rs 901.04 to travel 100 kilometres by train. Though fuel costs and airport fees are higher in India than in many other places, airlines often start selling fares below cost to fill capacity.

Travellers are benefiting from robust competition. AirAsia India recently launched and later this year Tata Sons will be starting a full-service airline called Vistara, which is a joint venture with Singapore Airlines.

The Wall Street Journal noted that with the rail hike two months ago, it is cheaper to fly by air than to travel by train to several destinations. However, buses rule the roost as the cheapest mode of transportation in India with an average of $5.75 or Rs 347.85 per 100 kilometres.

Though prices are fairly low, it's possible to find bargain. February is the cheapest month to travel, offering Indian consumers savings of 18% on flight prices on average, according to Skyscanner, a global travel search site. It studied three years of booking data to reach its conclusions. If you book 22 weeks in advance, you could save about 15% on average, Skyscanner said.

Looking at average flight prices in other countries, Finland and Switzerland come out on top with $138.90/Rs 8,402.39 and $125.07/Rs 7,564.04 per 100 kilometres respectively. Malaysia and South Africa are the second- and third-least expensive countries to fly in.