Two of the largest full-service carriers in the U.S. are American Airlines and Delta Air Lines, but being bigger doesn't always mean better. If you’re trying to decide between these two, this comparison can help you evaluate factors other than pricing. It’s especially helpful if you are considering building loyalty with one of these airlines’ rewards programs.

NerdWallet looked at the four areas below to determine what sets American and Delta apart:

Flight destinations and accessibility.

Frequent flyer program quality.

Airline credit card availability.

Overall in-flight experience.

Where they’re based and where they fly

American Airlines

Headquartered in Fort Worth, Texas, American Airlines flies to more than 350 destinations in 60 countries and territories. Together with its partners, it flies to more than 900 destinations in over 170 countries and territories. It is part of the 14-airline Oneworld alliance.

American Airlines’ major hub airports:

Charlotte, North Carolina.

Chicago-O’Hare.

Dallas-Fort Worth.

Miami.

New York (JFK and LaGuardia).

Philadelphia.

Phoenix.

Washington-Reagan National.

Delta Air Lines

Headquartered in Atlanta, Delta Air Lines flies to more than 275 destinations on six continents. Together with its alliance partners, it serves more than 1,000 destinations in 180 countries. It is one of the 19 airlines in the SkyTeam alliance.

Delta’s key airports in the U.S. are:

Atlanta.

Boston.

Detroit.

Los Angeles.

Minneapolis-St. Paul.

New York (JFK and LaGuardia).

Salt Lake City.

Seattle.

Winner for most options: American

American flies to more destinations on its own metal, but Delta is part of a bigger airline alliance, so it has a larger network of international destinations.

Travel credit card availability

American Airlines credit cards

American Airlines offers seven personal cards and two business credit cards with Citi and Barclays.

The American Airlines credit cards offer benefits like:

Welcome bonus miles after qualifying purchases for new cardholders.

2x miles for spending with American Airlines.

Other bonus spending categories, such as gas, groceries and restaurants.

Free checked bags and preferred boarding.

Admirals Club membership with the Citi® / AAdvantage® Executive World Elite Mastercard®.

Fee credit for TSA PreCheck or Global Entry with the Citi® / AAdvantage® Executive World Elite Mastercard®.

$25 annual Wi-Fi statement credit on American Airlines flights on the AAdvantage® Aviator® Red World Elite Mastercard®.

An annual companion certificate on the AAdvantage® Aviator® Red World Elite Mastercard®.

Annual fees range from $0 (American Airlines AAdvantage® MileUp®) to $595 (Citi® / AAdvantage® Executive World Elite Mastercard®).

In addition, every dollar spent on American Airlines credit cards also earn Loyalty Points, which are needed to earn American AAdvantage elite status. This makes it faster to earn status with the airline, even when you’re not flying.

Delta Air Lines credit cards

Delta offers four personal card options through American Express. Some benefits to expect, depending on the card, include:

2 - 3 miles per dollar on Delta purchases.

1 - 2 miles per dollar at restaurants and U.S. supermarkets.

1 or 3 miles per dollar at hotels.

Global Entry or TSA PreCheck fee credit with Delta SkyMiles® Platinum American Express Card or Delta SkyMiles® Reserve American Express Card.

Priority boarding and free checked bags.

$100 flight credit after spending $10,000 per year on the Delta SkyMiles® Gold American Express Card.

An annual companion certificate on the Delta SkyMiles® Platinum American Express Card or Delta SkyMiles® Reserve American Express Card.

20% back on in-flight purchases.

Terms apply.

Annual fees range from $0 (Delta SkyMiles® Blue American Express Card) to $550 (Delta SkyMiles® Reserve American Express Card). Terms apply.

Winner for airline credit card lineup: American

The fact that American Airlines credit cards earn Loyalty Points gives them an edge over Delta Air Lines credit cards. In fact, it’s possible to earn elite status by spending on an American Airlines co-branded credit card only.

Airline loyalty programs

American Airlines loyalty program

The AAdvantage program lets you earn miles and Loyalty Points for purchases through American Airlines and its partner airlines and for hotels, car rentals, vacation packages, cruises and spending on American Airlines co-branded credit cards.

Loyalty Points count toward elite status qualification, which comes with a host of benefits, including complimentary seat upgrades and increased mileage earnings. AAdvantage miles are redeemable for award travel.

Based on NerdWallet’s airline points value analysis, each American Airlines AAdvantage mile is worth about 1.7 cents. Miles expire after 24 months with no activity in the AAdvantage account.

When combining the miles earned per dollar spent with the value of miles, NerdWallet sees a 6.1% rate of return for each dollar you spend with American Airlines.

Delta Air Lines loyalty program

Delta SkyMiles members can earn miles by flying on Delta and its partner airlines, like Virgin Atlantic, Hawaiian Airlines and Air France. Members can also earn SkyMiles using a Delta credit card.

One con of the Delta SkyMiles program? Travelers don't earn SkyMiles or credit toward elite status on Delta basic economy fares. Meanwhile, American Airlines does allow a reduced mileage earning and Loyalty Points when flying on a basic economy fare.

Delta SkyMiles are valued at 1.5 cents each, and they never expire — a big plus when compared with American Airlines.

Members can redeem SkyMiles for flights, hotel stays, seat upgrades, access to Delta Sky Club lounges, experiences, merchandise and other travel purchases.

However, when redeeming miles for award flights, Delta can be more limiting compared with American Airlines’ broader selection of routes and more affordable award fares. When combining the miles earned per dollar spent with the value of miles, NerdWallet found a slightly lower 5.9% rate of return for spending with Delta Air Lines.

Winner for ease of miles: American

American Airlines has a slightly higher rewards rate and an easier way to earn elite status, so it edged out Delta Air Lines in NerdWallet’s annual ranking of best airline loyalty programs.

Extra fees

American Airlines

If you’re flying economy on American Airlines, you can bring one carry-on bag and one personal item aboard the aircraft. There’s no charge, so long as they fit inside the overhead bin or under the seat in front of you.

Checked bag fees start at $30 for the first bag and increase for additional bags. Some American co-branded credit cardholders, premium cabin passengers and those with AAdvantage status get the fee waived on their first checked bag.

Traveling with pets? You’ll pay a $125 fee to bring your pet onboard in an approved carry-on kennel. Unaccompanied minors incur an additional $150 fee, plus tax, each way, but additional siblings on the same flight are included.

Delta Air Lines

With Delta Air Lines, similar baggage rules apply for economy passengers. Travelers can bring one carry-on bag and a personal item on the plane at no additional charge. For standard checked baggage, you can expect fees starting at $30 for the first bag. Some credit cardholders, premium cabin travelers and travelers with elite status get the fee waived on their first checked bag.

Delta charges a $150 fee each way for up to four unaccompanied minors. For pets, travelers are charged a $95 one-way fee for carry-on pets, but they can only bring one aboard.

Winner for lowest fees: Tie between American and Delta

American and Delta essentially have identical fees, except for the carry-on pet fees.

In-flight experience

American Airlines

American offers lots of what you’ve come to expect from a modern airline, like high-speed in-flight Wi-Fi and a range of entertainment options including movies and music.

But on most AA flights, you have to use your own phone, tablet or laptop to access the entertainment, instead of a built-in screen on the seat back in front of you. There’s also no free texting on American Airlines, aside from app-based texting while connected to Wi-Fi.

Delta Air Lines

Delta offers a streamlined experience when it comes to in-flight entertainment. Delta Studio, the carrier’s entertainment suite, provides passengers on many flights with movies, TV series, music and podcasts from its built-in seatback screens.

Also, Delta provides travelers with free texting on iMessage, Facebook Messenger or WhatsApp, making it easy to stay connected while 35,000 feet in the air.

According to NerdWallet's analysis, Delta mishandles fewer bags, has fewer cancellations and diversions, and has less denied boardings, too.

Winner of the sky: Delta

Delta has a better reliability rating and onboard experience. The free messaging and seatback screens set Delta apart from American Airlines.

When considering Delta vs. American

When comparing the experience between Delta Air Lines versus American Airlines, American wins in more categories, including the ability to achieve elite status more quickly. Although it doesn’t have as many flight routes, Delta makes up for it with its superior in-flight experience and operations.

For most travelers, it will come down to which carrier is the most convenient. If both offer a lot of flights out of your home airport, then American makes it easier to earn elite status and fly to more places in its own planes at lower redemption rates.