Tuesday and Friday flights can help you avoid the rush earlier in the weekSundays and Mondays are the most expensive days to depart for domestic trips. If you can’t fly on the cheapest days, flying on Tuesdays or Fridays might also be a good option. The average airfare is about 12% lower than peak Sunday prices on these days.Nerdy TipMondays can still be a relatively expensive day to fly domestically. By departing on Monday instead of Sunday, you can expect to save only about $9, or about 3%.Wednesdays and Saturdays are the cheapest day to fly internationally