Frequent-flyer programs have been around for years — now-defunct Texas International Airlines was the first airline to offer loyal customers a benefits program, in 1979 — but they have only grown more convoluted with the passage of time. With points, status, partnerships, bonuses, and the ongoing question of whether they are actually worth your time and effort, it’s hard to keep track of all the moving parts.

The basic premise is simple. Travelers earn points (or miles) and achieve higher and higher levels of status in exchange for booking their flights on the same airline. In turn, they can use those points or miles toward things like free flights or hotel stays, and as they achieve higher status, they receive additional benefits such as complimentary upgrades, earlier boarding, special check-in lines and waived baggage fees on flights. In other words, airlines reward their passengers for their loyalty, and in turn, airlines benefit from repeat customers willing to keep spending to keep earning better benefits. Travel isn’t easy or cheap, so it’s a win-win for both parties.

American Airlines launched its AAdvantage program in 1981, and thanks to Texas International Airlines going by the wayside, it’s the oldest program around today. Other major airlines soon followed suit, each offering its own tiered status programs and offering miles or points in exchange for miles flown. Eventually airlines formed alliances with each other.

By offering a collective number of airlines, alliances provide travelers with access to a wider range of destinations to visit without losing out on the chance to accrue loyalty rewards. And airlines get to expand their reach by attracting flyers from other airlines which don’t service the same destinations. There are several alliances, so it helps to know which airlines work together. Here is a quick rundown of the top three:

Oneworld, reaching more than 900 destinations worldwide, includes 17 airlines: Alaska Airlines, American Airlines, British Airways, Cathay Pacific, Fiji Airways, Finnair, Hawaiian Airlines, Iberia, Japan Airlines, Malaysia Airlines, Oman Air, Philippine Airlines, Qantas, Qatar Airways, Royal Air Maroc, Royal Jordanian and SriLankan Airlines.

SkyTeam spans 945 destinations worldwide and includes 18 airlines: Aerolíneas Argentinas, Aeromexico, Air Europa, Air France, China Airlines, China Eastern Airlines, Delta Air Lines, Garuda Indonesia, Kenya Airways, KLM, Korean Air, Middle East Airlines, Saudia, Scandinavian Airlines, TAROM, Vietnam Airlines, Virgin Atlantic and Xiamen Air.

Star Alliance covers 1,150-plus destinations worldwide with 26 member airlines: Aegean Airlines, Air Canada, Air China, Air India, Air New Zealand, ANA, Asiana Airlines (soon to merge with Korean Air), Austrian Airlines, avianca, Brussels Airlines, Copa Airlines, Croatia Airlines, Egyptair, Ethiopian Airlines, EVA Air, ITA Airways, LOT Polish Airlines, Lufthansa, Shenzhen Airlines, Singapore Airlines, South African Airways, Swiss International Air Lines, TAP Air Portugal, Thai Airways, Turkish Airlines and United Airlines.

As loyalty programs evolved, they offered new ways to earn rewards. Most programs offer co-branded credit cards, like the American Airlines Citi / AAdvantage Mastercard or the Delta SkyMiles American Express card, but many also offer an online shopping component as part of the benefits package. Delta Air Lines just brought back a fan-favorite partnership with Starbucks so members can link their rewards account to earn miles for their coffee orders.

Anyone who flies knows how miserable it can be to wait for a flight with overpriced airport food, uncomfortable seating and crowds of people everywhere. Flying itself is stressful enough, so being able to escape it all for a little while proves priceless. It takes a lot of spending to earn those lounge privileges, but for those who fly often, it’s definitely worth it.

One can gain lounge access in various ways. The pay-per-use option lets you buy a visit regardless of program membership or status, and credit card lounges provide this luxury as a perk for holding a particular credit card. Airline lounges can be accessed by passengers flying in business and first class cabins, but they are also designed as a benefit for upper-tier loyalty program members. Alliance lounges welcome members with status in loyalty programs across the alliance.

Some lounges offer only the basics: bathrooms, snacks, beverages and a quiet place to wait for flights. But the higher your status tier, the higher the quality of lounges you can access with luxury amenities like wine bars, private cabanas and shower suites, spa treatments, and cigar bars. At the Air France La Première Lounge at Paris Charles de Gaulle Airport, you can even enjoy Michelin-starred dining while you wait for your next flight.

Loyalty programs continue to evolve. In 2023 British Airways introduced a new innovation for loyalty programs, offering reward flights, known as Avios Only Flights, which passengers can only book using Avios points, the loyalty currency of The British Airways Club. American Airlines allows AAdvantage members to use their miles to contribute to charitable causes through Miles for Global Health and Well-Being, and Delta Air Lines has started allowing customers to use their reward miles toward trip protection … all great ways to use miles if you don’t fly often and don’t expect to earn enough miles to exchange for free flights.

Some programs, such as American’s AAdvantage, allow members to gift or transfer miles to other program members. This comes in handy when it is time to renew your status for the coming year. If you are short on miles to qualify, someone else who may not fly as much or does not plan to use their miles can give you theirs to get you over the hump.

Air New Zealand’s loyalty program, Koru, also allows this type of transaction but only at the highest status tier. Koru, a recent overhaul of the airline’s previous version, Airpoints, is designed to more consistently match what travelers actually want from an airline loyalty program.

“We listened to our customers,” said Scott Wilkinson, chief commercial officer, Air New Zealand. “They told us they want a simpler program with clear, relevant benefits, and Koru is our response.” Our lives are often too busy to keep track of every detail of a program. Anyone who remembers the days when you had to redeem expiring miles for something like magazine subscriptions so you wouldn’t lose them will appreciate the importance of simpler programs with relevant benefits.

Miles that don’t expire are great for travelers who don’t fly frequently or who use multiple carriers (which makes it hard to build up enough miles for a free trip), but not all programs let you keep accruing until you are finally ready to use them. Delta Air Lines, United Airlines, Alaska Airlines, Hawaiian Airlines, JetBlue and Southwest do not impose expiration dates. Most other airlines require you to keep your account active (such as accruing more miles) within 12–36 months, depending on the airline, to avoid losing your points.

Some programs, such as American’s AAdvantage, let you keep your miles as long as you actively use a co-branded credit card. AAdvantage also rewards young flyers with miles that don’t expire until they turn 21, a step toward earning lifelong loyalty from future travelers.

Airline loyalty programs change constantly, and you could exhaust yourself trying to keep up with all of them. You might also find it equally frustrating trying to navigate every perk and loophole to get the biggest bang for your buck. Air New Zealand’s Scott Wilkinson hit the nail on the head when he summed up the airline loyalty program industry: “Travel means different things to everyone. To some, it’s returning home to family. For others, it’s work, time away or the chance to experience somewhere new. We want people to feel recognized in a way that reflects that.”

Travel isn’t cheap or easy, so it’s refreshing to know as the industry continues to evolve, it aims to improve the traveler experience.