Check all of the possible airlines
Carriers such as Southwest are often left out of booking engine search results. It pays to look deeper and include the major and secondary airlines in order to find more direct flights and cheaper fares. Price comparison sites are useful tools to search because they give fliers access to a wide range of carriers.
Focus on one-way pricing
Fares are no longer priced as round trips. Most routes no longer have "Saturday night stay-over" rule, and there is typically no penalty for using two different airlines. You can often get a better total trip price by looking at multiple airlines. Pricing is all about supply and demand for each specific route, and focusing on one-ways helps you spot the best value.
Round trips might be cheaper
In some cases (especially for international flights), a one-way can be more than a round trip. If this is the case, and you only need a one-way trip, then you're better off buying the round trip and simply discarding the return portion. Note – don't skip the original flight and only use the return leg, as your ticket might get canceled as a "no-show."
Consider the alternatives
Lower prices and less crowds can be found at alternate airports (secondary airports that serve a metropolitan area). Consider Ft. Lauderdale for Miami, Providence for Boston or Washington D.C. for Baltimore. Judge the cost savings versus the expense and time involved traveling to the alternate airport.
Fly the hubs
If you are trying to go from NYC to Los Angeles, then it's often cheaper to go through an airline's "hub" airport on the way. These busier airports typically have more capacity and more on-time flights.
Book early and book at the right time
Pricing is set by supply and demand, so if you wait too long, you will be met by high demand and low supply, a recipe for high prices. Book 60 or more days in advance for the best choice of rates and times. Airlines typically put out specials at the beginning of the week, so check early to get limited-time discounts. They also may lower fares during slower online times. Saturdays and late at night during the week are both good times to check fares. The worst time to book? Not surprisingly, it's during the traditional Monday-to-Friday work week.
Check the fees
To create a fair comparison between airline tickets, considers all of the checked and carry-on fees, as well as fees for food, Wi-Fi and other services. Southwest, for example, does not charge for first and second checked bags or change fees.
Travel on less busy days (remember the supply/demand) to get the best rates. Many airlines and booking engines offer dynamic calendars where you can see the pricing difference for choosing other dates.
Pick the right days
Saturdays, Tuesdays and Wednesdays are often the least busy and cheapest days to fly. Why? Because most business travelers leave on Sundays or Mondays and come back home later in the week.
Pick the right time of day
Flights that leave very early in the morning or late at night (the red-eyes) are typically cheaper than those during peak hours. A side benefit to very early flights is they are rarely late and don't require long waits on the tarmac for inbound/outbound traffic to clear up.
Related: How To Stay Healthy While Traveling
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