These frequent-flier junkies can often be identified by the stacks of credit cards bulging out of their wallets — and their eagerness to use one to pay for dinner. They are detail-oriented collectors who spend hours scouting out purchases that award the most points and managing spreadsheets that track their accounts.

The truly dedicated can rack up enough frequent-flier miles, or points, to fly first class and pay next to nothing for it. Stockpiling miles also gives travelers elite status, granting them access to premium check-in lines, seat upgrades, and airport lounges.

Frequent fliers will do just about anything to earn miles. Pull coupons off more than 12,000 cups of pudding. Buy millions of coins from the US Mint. Fly from Boston to Delhi and back again in less than 72 hours — twice.


Even as airlines and other companies get better at closing the loopholes, the most dedicated and frequent of frequent fliers always find more, driven not only by a love of travel, but also by a love of the game.

“It is kind of like a puzzle. You can unlock new clues,” said Brian Kelly, a Miami-based frequent-flier blogger known as The Points Guy . “This game can get addictive. And people go crazy.”

Frequent-flier miles were introduced by American Airlines in 1981 to reward customer loyalty. They have since become a huge moneymaker for airlines, which sell blocks of miles to credit card companies and other merchants to use as incentives for consumers to buy their products.US airlines raked in more than $8 billion from frequent-flier programs last year, according to IdeaWorksCompany, a Wisconsin airline revenue consultancy.

Airlines have made it more difficult to get free tickets (which still include some fees) in recent years by restricting schedules and upping the required miles. Next year, Delta Air Lines will base its frequent-flier program on ticket price rather than miles flown. Other airlines are expected to follow.


Delta spokesman Paul Skrbec said the change is to “reward customers that we value the most,” not thwart those who are “more astute in the rules of the programs.”

But the astute know other ways: test-driving cars, getting laser eye surgery, keeping money in online banks that offer miles instead of interest. Most of all, they use credit or debit cards that kick back a mile or two for every dollar spent.

To really rack up miles, the key is “manufactured spending”: using a card to buy the equivalent of cash, like a money order, then recycling that money back into your bank account.

“It can become an obsession once you realize you can go pretty much everywhere in the world for free,” said Tim Cahill, a 38-year-old economist in Boston.

Cahill usually has about 15 credit cards in his wallet, most of which will be closed within a year to avoid the annual fee. Contrary to conventional wisdom about opening new accounts, he says he has an excellent credit score. Perfect, in fact. 850 out of 850 the last time he checked.

One of his most labor-intensive effort to get miles came between 2008 and 2011, when the US Mint’s attempt to get more $1 coins in circulation became the Holy Grail for miles. The Mint offered free shipping, so Cahill whipped out his mileage-earning credit cards to buy as many coins as he could handle.


For more than a year, he spent Saturday mornings at the post office loading dock, filling his Jeep Cherokee with the coins he’d ordered. Then he’d deposit them in different banks, and use the money to pay off the credit cards he’d used to buy the coins in the first place. In all, he charged more than $1 million — and earned more than 1 million miles.

Many frequent fliers don’t like to talk publicly about these schemes, which they also call hacks, because they worry they will be perceived as doing something shady. Several who spoke to the Globe asked not to be identified for that reason.

“People who do this have no desire not to play by the rules, they just want to find out how to make the rules work for them,” said a North Shore resident who estimates he hasn’t paid full price for a ticket in 15 years. “We’re capitalists.”

His rule reworking has led to trouble a few times. He said he was “politely asked” to stop using Square Reader, a device that small business owners can attach to a phone to accept credit card payments. He linked the device to his business account and set it up so he could liquidate thousands of dollars worth of gift cards that he had purchased with a miles-earning card. He also took an online shopping site to small claims court after he didn’t get the frequent-flier miles promised for buying $10,000 in Home Depot gift cards.


Some people who bend the rules get kicked out of frequent-flier programs. A California musician who opened a Delta account for his cello, which flies in the seat next to him, was booted after racking up hundreds of thousands of miles.

One of the most legendary frequent fliers is “pudding guy,” a California civil engineer named David Phillips who in 1999 racked up more than a million frequent-flier miles by taking advantage of a promotion on Healthy Choice products offering 1,000 miles for every 10 UPC symbols, the bar codes found on many packages. Phillips spent just over $3,000 on more than 12,000 25-cent pudding cups, and redeemed the labels — with help from workers at the food pantries he donated them to — for tens of thousands of dollars worth of airline tickets.

Once people get a taste of flying for free, it’s tough to go back, frequent fliers say, especially if they have enough miles to fly first class from Hong Kong to New York, as one local frequent flier did, complete with champagne, caviar, and airline pajamas.

For most, flying free means calculating every purchase. TheBrookline author of the blog frequentflyermiles

101.com , known only as Mike, is known to buy his wife bouquets from florists offering miles. So when he splurged on two dozen red roses from Winston Flowers, the card read: “I love you so much that I got you the good flowers, not the ones that earn miles.”


His wife understands. She joined him on a crazy journey to maintain their executive platinum status at American Airlines, which requires flying more than 100,000 miles a year. Taking advantage of a deal offering double miles on a 15-hour Chicago-Delhi flight, they each made the trip twice in less than two months, going one at a time, while the other stayed home in Boston with their newborn twins — an experience that “scarred me for life,” the blogger said.

They shelled out $4,000 for four flights, using their status to upgrade to business class and spending only three hours in the Delhi airport before coming home. In the end, they raked in 65,000 miles apiece and kept their elite status, allowing them to upgrade seats, use special security lines, and access the airport lounge.

Eric Ding, a scientist at the Harvard School of Public Health, got into collecting miles when he was a postdoctoral student at Harvard and his Austrian girlfriend worked in Europe.He moved money in and out of a Fidelity brokerage account that offered 50,000 miles per $100,000 in deposits and went on manufactured spending sprees — using high-mileage credit cards to buy refillable debit cards to fund online accounts and purchase gift cards to shop in online malls that offered even more points.

Within a year he had 975,000 points; four years later, he has earned nearly 10 million. The ability to fly across the Atlantic for free to visit the woman who would become his wife saved their relationship, he said. Ding gave millions of miles to fly guests to the wedding, which had an airline theme, and has donated miles to friends with family emergencies and miles-earning magazine subscriptions to schools.

Ding, 31, flies around the world for free, often in first class, but he says that’s not the point of stockpiling miles, which he admits is a “weird hobby.”

“Unlike painting or pottery or stamp collection, at the end of the day airline miles give my family more freedom to see more of the world and visit loved ones,” he said. “That’s how I rationalize my crazy little obsession.”

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Maximizing miles

► Search out credit cards that offer miles for purchases, as well as signup bonuses. But don’t open a card if you can’t afford to pay the bill in full each month because the interest charges offset the rewards.

► Look for cards that offer discounts on travel-related purchases.

► Negotiate annual fees on mileage-earning cards. When the fee is due, call the company and tell them you are going to cancel. If it won’t waive the fee, cancel and sign up for a new card.

► Know your benefits. Keep a list on your smartphone of which cards offer extra bonuses at restaurants, office supply stores, etc.

► Use the shopping portal on an airline’s website to get extra miles for each online purchase.

SOURCE: Frequentflyermiles101.com

More coverage: American, US Airways tighten frequent-flier plans | Rabbi loses court case over frequent flier miles | Supreme Court limits suits over frequent flier miles | Delta will soon base flier points on cost | Inheriting frequent flier miles

Katie Johnston can be reached at katie.johnston@globe.com. Follow her on Twitter @ktkjohnston.