Considering getting an airline credit card? Think twice about how long you’ll keep it.

Personal-finance website ValuePenguin[1] analyzed 22 credit cards from the 10 largest U.S. airlines to find which have the most value.

One of the biggest findings: Airline credit cards have the most value in the first year. Airline cards often come with big sign-up bonuses but, in subsequent years, the value falls off considerably. The average sign-up bonus for the cards ValuePenguin analyzed was a whopping $400. Some cards on the higher end had bonuses worth much more.

Their declining value is an important consideration, especially as these cards have an average annual fee of $127, the analysis found. ...

image Courtesy of ValuePenguin Some cards were more valuable over time than others, the report said. The most valuable, according to this ranking: The Visa V, +0.10%[2] Signature card from Alaska Airlines ALK, +0.08%[3] which offers the most value because of its large sign-up bonus, companion fare discounts and checked bag fees. (The airlines and credit-card companies cited in this story did not respond to request for comment on ValuePenguin’s study.) Close behind was Delta’s DAL, +0.68%[4]   Platinum SkyMiles card, followed by the Citi/AAdvantage Platinum Select World Elite Mastercard (American Airlines) AAL, +1.06%[5] Southwest’s LUV, -0.23%[6]  Rapid Rewards Plus credit card and Southwest’s Rapid Rewards Premier credit card. Credit card Two-year net value (estimated, for a single person) Two-year net value, estimated for a married couple Two-year net value, estimated for a married couple with children Alaska Airlines Visa Signature $1,104 $1,897 $2,305 Platinum Delta SkyMiles $1,014 $1,892 $2,249 Citi/AAdvantage Platinum Select World Elite Mastercard $1,148 $1,803 $2,198 Southwest Rapid Rewards Plus $1,024 $1,579 $1,974 Southwest Rapid Rewards Premier $1,015 $1,570 $1,965 United MileagePlus Explorer $938 $1,442 $1,817 Gold Delta Skymiles from American Express $876 $1,380 $1,737 JetBlue Plus $789 $1,365 $1,759 AAdvantage Aviator Red Mastercard $827 $1,323 $1,695 Hawaiian Airlines World Elite Mastercard $595 $1,150 $1,224 To determine how much value single people and married couples could get out of the cards, ValuePenguin estimated how much they would spend each year

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