My wife and I recently embarked on our first vacation to Maui, Hawaii. One of the best parts was that our flight cost us nothing except airline taxes and fees totaling $11.20 round-trip for each of us. That’s because we used our Southwest Rapid Rewards® Plus Credit Card points to pay for my wife’s flight. My flight, meanwhile, was free—courtesy of Southwest’s Companion Pass, the holy grail of the card’s rewards program.

The Southwest Rapid Rewards Plus card is perfect for us because Southwest is our airline of choice, and the Companion Pass saves us money.

With the Rapid Rewards Plus card, you get 2 points for every dollar you spend on Southwest flights directly from the airline as well as Rapid Rewards hotels and car rental partners. If you’re like us and travel at least a few times a year, the points can quickly add up. You can also earn 2 points when using your card for local transit and commuting (including rideshares), internet, cable, phone services and select streaming services. All other purchases earn 1 point per dollar, which is pretty standard for most credit card rewards programs.

The Southwest Companion Pass

The main attraction of the Southwest Rapid Rewards Plus is the coveted Southwest Companion Pass. It’s the premier travel pass and primary reason I love this card as much as I do.

The Companion Pass allows you to designate a friend or loved one to fly with you for free—well, almost free. While your companion will not have to pay any airline charges, they will be responsible for the mandatory taxes and fees, beginning at $5.60 for a one-way flight or $11.20 round-trip.

What makes the Companion Pass so unique?

Unlike most cards, the Southwest Companion Pass is not only good for the year you earn it, but also for the entirety of the following year. Smart travelers can maximize savings by planning ahead and earning the Companion Pass in January. That means you and your companion could enjoy the pass for nearly two years.

Further, you can use the pass whether you are paying for your flight with points or with cash—a rare feature in the rewards space. That means you could use your Rapid Rewards points to purchase a flight for yourself and invite your companion to join you without using your points.

Best practices to earn points

You’ll need to earn 125,000 points, or fly 100 qualifying one-way flights, to receive the Companion Pass.

Here are a couple of tips to help you earn points fast:

Replace your debit card with your Southwest Rapids Reward Plus card

Anytime you would normally use a debit card to pay a bill or make a purchase, use your Rapid Reward Plus card instead. Use the card to pay for utilities, cellphone bills, streaming services, homeowners association fees, groceries, gas and any other purchase you can make with a credit card.

Take advantage of promotions

I can’t stress this enough: Email promotions are the hidden gem of this rewards card. Southwest is good about sending regular promotions with opportunities to earn bonus points. For example, one recent promotion offered 10,000 points—up to 50,000 total points—for each friend you refer who gets a Southwest Rapid Rewards credit card.

Earn points in multiples

Remember, you enjoy 2X points by booking your hotel and rental car with any Rapid Rewards partner, including Hyatt, Marriott and Radisson. You’ll also earn 2 points for each dollar you spend on local transit, commuting, internet, cable, phone services and select streaming services.

Shop using Southwest’s bonus partners

Shop at your choice of over 850 stores via Rapid Rewards Shopping to take advantage of bonus promotions. Currently trending stores include Macy’s, Apple and CVS Pharmacy.

Alternative Southwest cards

The low $69 annual fee for the Southwest Rapid Rewards Plus card is more than offset by the savings the card delivers. Nevertheless, Southwest offers higher-tier cards with more generous bonus offers and a faster track to A-list status.

I’m strongly considering signing up for the Southwest® Rapid Rewards® Performance Business Credit Card, which offers an 80,000-point sign-up bonus (after spending $5,000 on purchases in the first three months) and 9,000 anniversary points each year. Both the Performance Business card and the Southwest Rapid Rewards® Priority Credit Card extend four upgraded boardings each year, as well.

The bottom line

If you prefer Southwest Airlines over the competition, the Southwest Rapid Rewards Plus card is the perfect tool to begin earning perks with the airline. The annual fee is low, and the value offered by the benefits is high (especially when you factor in the much sought-after Companion Pass).

Consider the value of the Plus card if you want to save money on your future travels. Soon, you could be booking flights for two while paying nothing but modest airline taxes and fees.