When it comes to getting the most out of frequent flyer programs, loyalty pays. But in some cases, it pays better than others.

Personal-finance website WalletHub has taken a look at the 10 largest domestic airlines loyalty programs, ranking them on 23 different metrics including the value of a rewards point, blackout dates, and the ease of earning elite status.

Topping the list was Delta Airlines SkyMiles program, which nabbed the top spot for the fourth year in a row. Second and third ranked programs were United’s and Jet Blue’s, respectively.

When it comes to the value of rewards points or miles, however, Delta did not rate as highly as some of its competitors. Hawaiian Airlines, which earns the average flyer $15.97 for every $100 spent, ranked the highest on that metric, followed by Alaska ($13.59 for every $100), Frontier ($10.68), and then Delta ($10.54).

Delta was, however, one of only two airlines whose miles do not expire because of inactivity (the other was JetBlue). Its rewards program also lets you earn and redeem miles with 40 partner carriers.

How much you travel matters, too. If you only take one or two trips a year, you may not be best served by the same program than someone who shuttles back and forth across the country every week.

To help, WalletHub also offers a calculator that allows you to “customize the results of the study based on your own airline budget.”

The top five airlines are below. To see a detailed breakdown of the ranking metrics, as well as the custom calculator, head over to WalletHub’s website.

AirlineValue of milesDo miles expire?Partner carriers
Delta$10.54No40
United$7.94Yes39
JetBlue$4.27No7
Southwest$9.19YesNone
Hawaiian$15.97 Yes6

Note: The value of miles or points is for an average flyer