When you're sitting to book your international flight tickets to Central or South America, you must book them at least 215 days in advance. Thirty weeks or seven months in advance. However, to be a little more certain and to have a painless visa process and sort out other travel documents, you should try for an earlier date. Both the continents are vast and need proper planning before you can take your trip. Hence, before booking your tickets, it is important that you do thorough research on the places that you plan to visit when in Central or South America. For the same, the least delay to book your international flight tickets to these destinations shouldn't exceed 120 or 18 weeks in advance. During the four months following your ticket booking, you can get your travel papers and documents in order.