Are airline credit cards worth it? Yes, but there’s one big catch.

“It’s the only airline card I will keep,”says Goodman, a systems administrator from New York. “The checked bag benefit and lounge passes are nice but I get the most benefit out of the added Saver award space you get with the card. I use my miles for last-minute trips to visit friends in the bourbon community.” 

With a $0 annual fee the first year and just $99 after that, it’s easy to see why the United MileagePlus Business card is a keeper for Goodman. But are airline cards always worth it? Some are definitely not worth the hype. Let’s dig a bit deeper so you can see when it makes sense to apply for an airline credit card and when you should fly on by. 

If you check bags, airline cards are a no-brainer

Unless you have airline status or only fly Southwest Airlines, you will have to pony up every time you check a bag on an economy class ticket to the tune of up to $40 per bag, per flight. The right airline credit card, even some with an annual fee under $100/year, can grant you a free checked bag every time you fly. Just one round trip with a companion will more than make up for your annual fee. 

“Getting a free checked bag typically covers my annual fee each year,” says Harrison Pierce, a writer and credit card expert. “As long as I take a few trips throughout the year, the baggage benefit is enough to offset the $150 annual fee, making all the other benefits an additional bonus.”

Airline loyalty cards can be a double-edged sword

If you are loyal to one carrier, having a co-branded airline card may make sense because the money you spend on the card may count toward your flight status. But not every airline makes it easy to earn status without actually spending money on airfare. The ones that do certainly earn a place in your wallet if the perks that come with status are important to you. 

This is especially true for American Airlines, where a dollar spent on many cards is exactly equal to a dollar spent on an airline ticket. Southwest Airlines also gives you status-earning points on card spending, which is helpful if you are trying to earn the 135,000 Rapid Rewards required for the Companion Pass.

Joseph Hostetler, a credit card writer, used the Companion Pass for an important purpose. “I used the Southwest Companion Pass to save over $900 on airfare when traveling to Cancun for my honeymoon,” says Hostetler. Used properly, the Companion Pass, which allows you to take someone on any Southwest flight for just taxes and fees, could save you thousands. 

On other airlines such as United and Delta, you’ll earn miles with your credit card spending, but not every single mile will count toward status. Both airlines use somewhat complicated formulas to determine exactly what will get you to the next run on their ladders. So in these cases, the cards are probably nice to have rather than necessary. 

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Welcome offers are golden, but beware of fool’s gold

Airline credit cards often come with generous welcome offers that promise to have you flying in no time. And done well, an initial burst of 70,000 miles or more can feel golden. But those miles tarnish if you can’t redeem them. My Delta SkyMiles have turned green because the redemption prices have been outrageous on trips I wanted to take.

I am sitting on about 200,000 Delta miles that I am having trouble spending, even with the TAKEOFF15 benefit—providing a 15% discount when booking award travel on Delta flights using miles—I have with the Delta SkyMiles® Platinum American Express Card. Over the summer an economy flight to Madrid priced out at 85,000 SkyMiles after the discount. The exact same flight priced out at 15,000 miles using Flying Blue.

If you can be flexible and take advantage of sales like Delta’s SkyMiles award deals or Flying Blue’s Promo Rewards there’s tremendous value to be had in welcome bonuses. But you may find that flexible points programs like Chase Ultimate Rewards or Amex Membership Rewards, which let you transfer points as needed to airline programs, align better with your travel goals. 

The takeaway

As with almost everything about credit cards, the answer to whether airline cards are worth it isn’t quite black and white. It’s an easy yes if you know you like to check a bag and know you fly one airline enough to cover the annual fee. 

But advice gets murkier when you are looking at cards from a redemption perspective. Earning miles in one program locks you into that airline and its partners, which can make spending the miles both more difficult and more expensive in the long run. 

If you consistently see affordable ways to spend your miles, then spending on an airline card makes sense. But be aware that you don’t own your miles, the airline does, and keeping all of your miles in one basket makes you more vulnerable to award seat shortages and devaluations. 

So the best advice may be to get and keep an airline card for the benefits, but don’t use it for everyday spending. You’ll get a lot more bang for your rewards by earning them in a flexible program and transferring miles to your airline when you need them.