The sweet spot to book a domestic flight is between 28 – 49 days in advance, while international flights should be booked three to four months in advance for the lowest prices.

The "best day" is a moving target, but the consensus among travel experts is that Tuesdays and Wednesdays are the sweet spots for booking flights and hotels. Most airlines launch sales on Monday nights or Tuesday mornings, prompting competitors to match prices by mid-afternoon. For the actual travel days, flying on a Tuesday or Wednesday is almost always cheaper than a Friday or Sunday. However, the "booking window" is arguably more important than the specific day of the week. For domestic trips, booking 1 to 3 months in advance is ideal, while international travel usually requires a 2-to-8-month lead time. Using tools like Google Flights to track price fluctuations is often more effective than strictly adhering to a "Tuesday booking" rule, as algorithms have become increasingly unpredictable.