How to Use the Southwest Low Fare Calendar to Get the Best Possible Deal on Flights (Video)

Booking a vacation is always exciting — researching all the great food you will indulge in, looking up fun activities, and anticipating days dedicated to relaxation. But there's one part that can be a little stressful: staying on budget.

Airfare is one of the biggest expenses of any trip. But if you're a little flexible in your travel days, there are ways to make sure you get the best bang for your buck, and Southwest Airlines' Low Fare Calendar is a great tool to ensure that happens.

"We view the easy-to-use calendar as another way that we are able to extend our Southwest Hospitality to customers," a Southwest spokesman told Travel + Leisure in an email.

By putting in the month you want to travel, you can see the cheapest days to both leave and return on, making it easy to compare different travel periods. You can search by one-way, roundtrip, and even multi-city fares, as well as search by different fare types like the lowest possible rate, anytime fares (which are refundable and changeable), or Business Select.

"Whether they are looking to travel on certain days of the week or looking for the best prices across an entire month, we encourage customers to check out our Low Fare Calendar to find some of our lowest fare offerings," the Southwest spokesman added.

The Low Fare Calendar also takes the guesswork out of paying with points by allowing you to search for a flight by how many Rapid Rewards points each ticket would cost. Plus, you can get a Southwest Companion Pass after earning 125,000 points in a year.

And if you're thinking of going somewhere but don't know when to go, you can toggle between months to decide when the best, and least expensive, time to fly is.

A search of flights from New York's LaGuardia Airport to Charleston, South Carolina, for example, reveals a roundtrip flight for as low as $135, which leaves more money to splurge on meals (Charleston is one of the best food cities in the country, after all).

The first step in going on a vacation is deciding to actually go, and the next step is often figuring out when to go and how much it will cost. So on your next trip, use the Low Fare Calendar to take some of the uncertainty out of the equation.