To find the cheapest air ticket from Chongqing to Xi'an, first of all, you need to determine your flight itinerary and the approximate time of your trip. Of course, the more time you have, the greater your options will be. It is best to determine within a range, usually one week. It's fine if it's within the limit, so the price is lower and the ticket reservation staff can make it easier for you to check.Next is the time to book tickets. Isn't the earlier the better?Of course not, different routes have different best times to book tickets.Normally, if you book a flight for this month, you can get the best price at the beginning of the month.There are some popular cities, such as air tickets to Guangzhou, Shenzhen and Beijing, which we call main lines.For routes like this, generally 5-9 days in advance are sufficient. If it is too early, the price will still be relatively high, because the airline has not yet released the discount position.There are also some routes where airlines will only offer discounted air tickets 3-5 days in advance. This can only be found out by consulting the agent.There are also some group tickets that are generally booked in advance, but tickets can only be issued 1-2 days in advance.If you are booking a flight for next month, it is best to book it at the end of this month or the beginning of next month, so that you can book the flight with the lowest discount.