What to buy, what to avoid at the airport: Seven tips for strategic duty-free shopping

2. If you're in the market for makeup, look for freebies.

Cosmetics brands sweeten deals by creating special travel-size versions of popular items or offering freebies with your purchase as a perk, Smyth says. Your standard-size lipstick may cost about what you'd pay at home, but at duty-free, the brand may throw in an extra gift.

"It's useful in terms of maximising the value at a duty-free," Smyth says.

The sales associates will be the most up-to-date on brand promotions, so ask them about potential gifts with purchase before you start browsing. You can also go online to Duty Free Hunter or, for travellers going to the UK or Germany, World Duty Free, to find news on travel retail sales.

3. Find items you can't buy anywhere else, especially spirits.

For some brands, making limited-edition items available only in duty-free stores is a way to reel in new and existing customers.

"What you've seen more and more is the use of exclusives," Richardson says. "There will be certain perfumes or drinks brands in particular that you can only get when you travel. Johnnie Walker will create a whiskey that is only available in certain airports, so that way they're giving travellers a reason to make sure they go in the shop."

Spirits brands, for example, may release multi-bottle series for these stores to tempt spirits connoisseurs. Like playing Pokemon, you may be compelled to try to catch them all.

"The idea for now is that we need to offer passengers something different that you can't ordinarily get," says Manjot Riyait, head of marketing for Global Travel Retail at William Grant & Sons Global Brands, the independent spirits company responsible for brands like Glenfiddich, Balvenie and Hendrick's gin. For collectors who already have staples from a spirits company's core range, scoring a bottle at duty-free you can't get at liquor stores, like the Balvenie Triple Cask range, can be a huge win.

Booze companies aren't the only ones to make moves like this. Cosmetics companies and fashion labels are also known to release travel-retail exclusives. For example, the French fashion brand Chloe just released a four-piece capsule collection for DFS, a luxury travel retailer with duty-free shops in 11 major airports.

4. Candy is a nice present, but you won't save cash on it.

Even though sweets make up a large chunk of real estate in duty-free stores, it's not there because it's a fantastic deal only found past the security checkpoint.

"With confectionery, there isn't a huge saving, because the price points are much smaller," Richardson says.

He says prices on sweets will vary where you go around the world due to local market factors, so you may be able to find Toblerone cheaper than you would at home. The biggest perk of buying desserts at duty-free is that it's an easy last-minute gift idea. Many candy brands will stock the shops with packages that are ready to be presented as gifts.

5. Take advantage of international brands you can't find at home.

Duty-free stores study their customer base's demographics and fill their shelves with items curated to appeal to groups travelling through certain airports. That means fliers may encounter products they wouldn't normally at their hometown mall.

"You might see Asian brands that you can't get anywhere else in America, but you can get them at the San Francisco airport, because there's a demographic travelling through there that they need to service," Richardson says.

6. Skip the sunglasses.

As with chocolates and candy, the most persuasive case for shopping for sunglasses at the airport is the convenience. If you forgot your Ray-Bans at home while en route to Cancun, at least you can get some before you hop on the plane. Richardson isn't sold on buying shades at duty-free for cost purposes, though, saying there's no massive bargain.

"You may get exclusive lines, but they'll be minimal in terms of saving," he says. "If you dig around on the internet, I would think you'd find them for the same sort of price."

7. Research, because some items may not be cheaper at duty-free at all.

Retailers may offer higher discounts in some markets than in others. For example, a bottle of Lagavulin 16-year-old Scotch whisky at Singapore's Changi Airport runs for the equivalent of about $US90, while it can be had for only $US60 at London Heathrow. Sometimes prices vary within a single airport. According to findings from the Points Guy's research, duty-free prices may even differ from terminal to terminal. If you have time before your flight, it may be in your best interest to compare prices among different concourses. But calculating whether an item at duty-free is less expensive than it is elsewhere is a complicated dance.

"Trying to compare savings between, say, Singapore and New York is near impossible, because there are so many factors at play," Richardson says. "It has so much to do with where you're shopping in the world."

If you have brands in mind you're hoping to shop for at the airport, Smyth recommends taking the time to note how much you normally pay for those brands before you leave for your trip.

"Do research and give yourself time to understand what the offer is. Then you can maximize the value," Smyth says.

TNS

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