American vs. Delta vs. United - we compared the 3 most popular airline credit cards

Welcome bonus: Earn 40,000 United miles after you spend $2,000 in the first three months, and earn an additional 25,000 miles after you spend $10,000 total in purchases in the first six months.

Annual fee: $0 introductory annual fee the first year, then $95

Earning miles: 2 miles per dollar spent on United purchases and at restaurants and on hotel stays, 1 mile per dollar on everything else

Top benefits: Free checked bag, priority boarding, two complimentary one-time United Club lounge passes each year, up to a $100 application fee credit for TSA PreCheck or Global Entry, access to additional award space, no foreign transaction fees

The United Explorer Card from Chase is a solid option for United flyers. Like the other airlines' sub-$100 cards, the United card offers a free checked bag for the cardholder. Up to two traveling companions booking at the same time can also get a free checked bag each. This is especially useful since United raised the price of a checked bag to $30.

Unlike the other airlines' cards, though, you'll have to actually buy the tickets with the United card in order to get the free checked bags — simply having the card open and tied to your account isn't enough.

For those who don't have luggage to check, the card offers priority boarding for everyone on your reservation — you'll get this benefit even if you pay for the tickets with another card. By boarding earlier, you can make sure to snag overhead space for your carry-on.

One excellent perk with the United card is that you'll get two complimentary one-time passes to United Club lounges each year. If you get to the airport early or end up dealing with a delay, you can head to the lounge and enjoy free snacks, drinks, Wi-Fi, and more comfortable seating than what you'd find in the terminal.

When you spend $25,000 in a calendar year, you'll also get a PQD waiver — PQDs, or "Premier Qualifying Dollars," count toward earning elite status with the airline. When that requirement is waived, you'll earn status just based on how much you've flown, rather than a combination of how much you've flown and how much you've spent that year.

The card earns 2 miles per dollar spent on all United purchases, and it also earns 2x miles on all dining and hotel spending. It will continue earning 1x mile on everything else. There are no foreign transaction fees.

Other features include a fee credit to cover the cost of enrolling in Global Entry/TSA PreCheck, and a 25% discount on all in-flight United purchases.

One unique — but unpublished — perk of the card is that having it helps you access additional United award space. That means that you'll have an easier time finding the flights you want when it's time to actually use your miles.

Click here to learn more about the United Explorer card.

Welcome bonus: Earn 50,000 American Airlines miles after you spend $2,500 in the first three months.

Annual fee: $99; waived for the first 12 months

Earning miles: 2 miles per dollar spent on American Airlines purchases, at gas stations, and restaurants, 1 mile per dollar on everything else

Top benefits: Free checked bag on domestic flights, preferred boarding, 25% off in-flight food and beverages, no foreign transaction fees

50,000 miles (or at least 52,500, when you factor in the miles you'll earn for completing the minimum spending requirement) can get you far on American Airlines — as long as you can find "SAAver" availability. Based on American Airlines' award chart, it's nearly enough miles for a round-trip flight to Europe or South America during peak season, a one-way ticket to Europe in business class, or at least two domestic round-trips (or more, depending on the distance).

The Citi/AAdvantage Platinum card earns 2 miles per dollar spent on American Airlines purchases, and Citi also recently added a few new bonus categories — new card members will earn 2x miles on restaurants and at gas stations, too. You'll earn 1 mile per dollar on everything else.

The card comes with a suite of useful benefits for American Airlines flyers.

You and up to four companions traveling on the same reservation each get a free checked bag on domestic flights (since American Airlines is a full-service carrier, most international flights include the first checked bag for free). Because the first checked bag is usually $25 each way, this benefit can save you $50 on a round-trip itinerary.

In addition, you and everyone on your reservation get preferred boarding — joining an earlier boarding zone. That gives you more time to settle in — and earlier access to the overhead bins, so that you can make sure you'll have room to store your bag.

A small, but useful new perk: When you spend $20,000 or more on the card in a card membership year, you'll get a $125 discount on your next American Airlines flight (that's in addition to the miles you'll earn on those purchases).

The card also offers a 25% discount on in-flight purchases, such as food and drinks, and access to discounted mileage award flights.

Each card has strengths and weaknesses. Let's look at each:

Delta: the Gold Delta SkyMiles card from American Express

Pros:

• Free first checked bag for you and any traveling companions, regardless of whether or not you use the card to buy your tickets
• Priority boarding
• Discounted day passes for Delta Sky Club lounges — though this benefit will be discontinued in 2020
• Discounts on in-flight purchases

Cons:

• No bonus earning categories (besides Delta purchases), but this is changing in 2020, when the card will offer 2x miles on US supermarket purchases and at restaurants
• No extras (like a discount on flights, extra points, or help toward elite status) if you spend a lot on the card in a year, but in 2020 the card will add a $100 Delta flight credit when you spend $10,000 in a calendar year

United Airlines: the Explorer Card from Chase

Pros:

• 2x miles on dining and hotels, as well as on United purchases
• Two complimentary one-time United Club lounge passes each year
• Priority boarding for you and your travel companions
• Discount on in-flight purchases, Global Entry/TSA PreCheck credit
• Access to additional saver-level award seats

Cons:

• To get the first checked bag free, you'll have to use the card to buy your tickets
• The free checked bag is only extended to up to two traveling companions — that's not helpful if you're traveling with a family of four

American Airlines: the Citi/AAdvantage Platinum Select

Pros:

• 2x points on dining and gas — not just on airline purchases
• Offers a solid sign-up bonus
• Free first checked bag for you and up to four traveling companions, regardless of whether or not you use the card to buy your tickets
• Priority boarding
• $100 discount on an American Airlines flight if you spend $20,000 in a year
• Discount on in-flight purchases

Cons:

• No lounge passes or discounts
• No spending bonus that counts toward elite status

The best card is the one for whichever airline you find the most useful. Although there are some differences between them, each of these cards comes with a version of free checked bags and priority boarding, which are the most valuable reasons to have the cards. Plus, they help you earn more miles — and quickly.

However, if you're ambivalent about your choice of airline, the Citi/AAdvantage card for American Airlines is probably the most appealing card right now.

Between 2x miles on several categories and a solid sign-up bonus, this card represents a great value. However, keep in mind that it's always possible that the sign-up bonus increases at some point in the future, although there's no guarantee.

However, starting on January 30, 2020, the Gold Delta Amex will give the Citi AAdvantage card a run for its money thanks to the introduction of new bonus categories and perks.

As benefits continue to be added and removed — and, crucially, as sign-up bonuses and welcome offers fluctuate — this evaluation could always change. One way or another, an airline card is a must-have and represents significant value for anyone who flies even just a few times a year.

Click here to learn more about the United Explorer card. Click here to learn more about the Gold Delta SkyMiles card.

This content is not provided by the card issuers. Any opinions, analyses, reviews or recommendations expressed here are those of the authors' alone, and have not been reviewed, approved or otherwise endorsed by any issuer.

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