If you love saving money on travel as much as I do, you need to stop what you are doing right now. A massive travel deal just dropped, and it is easily one of the best promotional events we will see all year. Southwest Airlines is offering an incredible 40% discount on base fares for travel spanning late autumn all the way into early spring of 2027.

I constantly monitor airline promotions, and a discount of this magnitude does not come around often. Whether you want to plan a cozy mountain getaway, visit family for the upcoming season, or escape to a sunny beach, this promotion provides the perfect opportunity to book those flights for a fraction of the usual price. However, you must act quickly because this booking window closes on September 17, 2026. Below, I will break down everything you need to know about this promotion, how I am personally using it, and which credit cards you should use to maximize your return.

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Understanding the Details of This Incredible Promotion

Before you rush over to the booking engine, we need to examine the specific rules of this promotion so you can maximize your savings. Southwest Airlines is slashing base fares by 40% when you use the designated promotional code during the checkout process. This discount applies to both one-way and round-trip bookings, which gives you immense flexibility when planning your itinerary.

To take advantage of this deal, you must book your flights by September 17, 2026. The eligible travel window opens on October 5 and extends all the way through March 3, 2027. This broad travel window covers several months, allowing you to plan autumn weekend trips, winter ski adventures, and early spring retreats. Nevertheless, keep in mind that the discount applies strictly to the base fare. Consequently, any government-imposed taxes and airport fees remain unaffected by the 40% reduction. Fortunately, Southwest taxes are usually very low, meaning you will still see massive overall savings on your final ticket price.

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How I Am Personally Maximizing This Sale

I love this promotion because it perfectly aligns with my personal travel goals for the upcoming winter. I am already looking at the route map to book a ski trip to Salt Lake City, Utah, as well as a warm escape to Costa Rica in January. Because Southwest serves an array of international destinations alongside its robust domestic network, you can apply this discount to tropical hotspots in the Caribbean, Mexico, and Central America.

To make the deal even sweeter, this 40% discount applies to point redemptions as well. When Southwest runs a base fare promotion, the points price of the flight drops proportionally to the cash price. I love using my Rapid Rewards points during these sales because my points stretch significantly farther. Instead of spending 15,000 points on a one-way flight, I can often secure the exact same seat for just 9,000 points plus the standard $5.60 in taxes. If you have a stash of Southwest points sitting in your account, now is the absolute best time to burn them.

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The Best Credit Cards to Pair With This Deal

To truly master the art of travel hacking, you should never pay for a flight with just any credit card. You must use a card that earns valuable points and protects your journey. Fortunately, we have several outstanding credit card options that pair beautifully with this Southwest sale.

First and foremost, I highly recommend the Chase Sapphire Preferred® Card. I love this credit card because it provides a stellar 2x points on all travel purchases, including Southwest flights. Furthermore, Chase Ultimate Rewards points transfer directly to Southwest Rapid Rewards at a seamless 1:1 ratio. If you do not have enough Southwest points in your account right now, you can instantly transfer points from your Chase account to lock in these 40% discounted flights before the September 17 deadline. Additionally, the card offers robust trip cancellation and interruption insurance, which will protect your discounted vacation if plans go awry.

If you want premium travel perks, you should look at the Chase Sapphire Reserve®. This card elevates your earning potential by awarding 3x points on travel purchases. It also features a $300 annual travel credit that automatically offsets your flight purchases, which could make your discounted Southwest flight completely free. Moreover, the card grants you access to premium airport lounges, making your travel day far more comfortable.

Finally, do not overlook the co-branded Southwest credit cards, such as the Southwest Rapid Rewards® Priority Credit Card. I love this card because it offers a $75 annual Southwest travel credit and four upgraded boardings per year. When you use a co-branded Southwest card to purchase these discounted flights, you earn up to 3x points per dollar spent directly on Southwest purchases. This helps you build your point balance back up for your next adventure.

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The Secret Southwest Hack: Rebooking Your Existing Flights

One of the greatest benefits of flying with Southwest Airlines is their industry-leading flexibility. Southwest never charges change fees or cancellation fees. Consequently, this promotion offers a golden opportunity for travelers who have already booked flights for the October through March window.

If you already have a Southwest flight booked during these travel dates, you should immediately check the price of your flight with the 40% discount code applied. If the price has dropped, you can easily “change” your flight to the exact same itinerary on the Southwest website. If you originally booked using cash, Southwest will issue the difference as a future flight credit. If you booked using Rapid Rewards points, Southwest will instantly deposit the price difference back into your account. I regularly perform this trick during major sales, and I have saved tens of thousands of points over the years without changing my travel dates by even a single hour.

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How to Earn the Highly Coveted Companion Pass

This 40% off sale can also serve as a powerful tool to help you earn the Southwest Companion Pass, which is widely considered the single best deal in the entire travel industry. The Companion Pass allows you to bring a designated friend or family member with you on any Southwest flight for just the cost of taxes and fees.

To earn the Companion Pass, you must fly 100 qualifying one-way flights or earn 135,000 qualifying points in a calendar year. Because you can book so many cheap cash flights during this sale, you can easily rack up the necessary flight segments to secure your pass for the remainder of 2026 and the entirety of 2027. Furthermore, when you hold a co-branded Southwest credit card, you receive a boost of 10,000 Companion Pass qualifying points each year, bringing you that much closer to the finish line.

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Step-by-Step Instructions to Claim Your 40% Discount

Booking this deal is incredibly simple, but you must follow these specific steps to ensure the system applies the discount.

1. Navigate to the official Southwest Airlines website or open the Southwest mobile app. 2. Enter your desired departure and arrival cities, along with your travel dates between October 5 and March 3, 2027. 3. Locate the promo code box on the search widget. Enter the active promotional code provided on the Southwest homepage for this specific 40% off event. 4. Select your flights. You will see the discounted price highlighted in the search results, showing you exactly how much money or points you are saving. 5. Complete the checkout process using your favorite travel rewards credit card, such as the Chase Sapphire Preferred, to maximize your points and obtain travel insurance.

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Act Quickly Before the Best Seats Disappear

While the booking deadline is September 17, 2026, you should not wait until the last minute to secure your tickets. Southwest allocates a limited number of discounted seats to each flight. Once those promo-eligible seats sell out on a specific route, the price will revert to the standard fare. Therefore, you should search for your flights today to guarantee the best selection of flight times and destinations. Happy traveling, and enjoy your incredibly cheap flights!