International Airfare — México
The trick to saving money on airfare is to travel during the off seasons, to hunt for bargains from different sources, and to not be afraid to ask for student and senior discounts.
Airfares to tourist destinations in México go up during the high seasons — winter holidays, around Christmas and New Year; Easter holiday, from late March until early April; and summer months, from mid-June until early September. And, depending on the destination, there may be a slight increase in airfare on weekends and Fridays. Non-tourist destinations — such as México City, Guadalajara, and Monterrey — show little, if any, seasonal fluctuation in airfares.
In general, booking tickets well in advance (21+ days) and having fixed dates save on airfare; this is especially true, during the high seasons. Booking a round-trip ticket is always going to be cheaper than putting a trip together with two or more one-way flights (open-jaw ticket), unless it's done with an airpass or a round-the-world ticket.