Hot Packs: The Pocket Warmer Everyone Carries

Watch a line at a Seoul bus stop on a January morning and you will see hands disappear into coat pockets and stay there. Inside most of those pockets is a hot pack, 핫팩 in Korean, the English words borrowed whole. It is a small pouch of iron powder that warms up when air reaches it, and it is as ordinary a winter object here as an umbrella is in the rainy season.

You will meet two main kinds. The classic is the pocket type you shake and knead until it warms, then hold for hours. The stick-on type has an adhesive back and goes on the outside of a layer of clothing, at the lower back or between the shoulders; the packets themselves say not to stick it straight onto skin. There are also slim versions made for the soles of shoes, which make a real difference on a long day of walking palace grounds or standing at a winter festival.

The cold arrives early in the shops. When temperatures dropped sharply in the first week of this October, Yonhap reported that disposable hand-warmer sales at the convenience store chain GS25 rose more than elevenfold over the previous week. By December the packs sit beside the counter at nearly every convenience store, in stacks at Daiso, in supermarkets and at many pharmacies, sold singly or in multipacks for little more than the price of a canned coffee.

Many people now also carry a rechargeable hand warmer, a smooth palm-sized gadget that heats at the press of a button and often doubles as a phone battery. It is a nice thing to own, but it contains a lithium battery, which changes how it can fly.

Long Padding: Korea's Winter Uniform

Step out of a subway exit in December and the street looks like a slow parade of sleeping bags. The knee-length padded coat, 롱패딩 or long padding, is the closest thing Korea has to a winter uniform, worn by students, office workers and grandparents alike, usually in black, navy or cream.

The look took off in the run-up to the 2018 PyeongChang Winter Olympics. In November 2017, an officially licensed long padded coat went on sale at Lotte Department Store, and the Kyunghyang Shinmun reported that 800 coats sold out within 15 minutes of opening, followed by a restock of 3,000 that was gone before it went on sale. Outdoor brands posted record months that winter, and the long silhouette spread to fast-fashion chains, children's clothing and womenswear. It has stayed ever since.

Once you spend a day in the city, the logic is easy to see. Seoul's cold is often dry and windy, much of a winter day is spent waiting, at crossings, bus stops and outdoor stalls, and a coat that covers the thighs keeps you warm on a cold stadium seat or a park bench. It also zips over whatever you are wearing, so it suits a trip where you go from a heated cafe to a frozen riverbank and back.

The coats are bulky in a suitcase, which is why some visitors buy one in Seoul. Outdoor-brand shops, fast-fashion chains and department stores all carry them through the season, and you will see plenty of choice from late October onward.

The Layer Underneath: Thermal Innerwear and Heated Floors

Under the long padding, most people in Korea wear something thin. Thermal innerwear, 발열내의, is a winter staple, and many people simply call it heattech after Uniqlo's well-known line. Korean labels sell their own versions, among them SPAO, Musinsa Standard, JAJU and BYC, and every December the racks fill with long-sleeve tops and leggings in skin tones, black and grey.

The reason is underfoot. Korean homes, guesthouses and many restaurants are heated through the floor by ondol, the radiant heating system that has warmed Korean rooms for centuries in one form or another, and cafes, subway trains and department stores tend to run warm. You will move between biting cold and real warmth a dozen times a day. A thick sweater makes that miserable. A thin base layer under a coat you can take off does not.

That rhythm of peeling layers off and putting them back on shapes small habits you will notice. Cafes keep knee blankets by the window seats. Many barbecue restaurants hand you a plastic cover for your coat, or have bench seats that lift open for storage, so your padding does not come home smelling of grilled pork. And in winter, a warm floor is where people actually sit.

Warm Spots Built Into the City

Korea's cities quietly help with the cold, too, and once you know where to look, a winter walk feels easier. Start with the bus stops. Seoul has spent the past several winters fitting its shelters with heated seats, and in 2023 the city announced an expansion that would put them at more than 80 percent of its bus stops. Sit down on a freezing morning and the bench is warm.

Several Seoul districts also put up wind shelters at busy stops each winter: clear tents or screens you can step inside while you wait. They go by local names, such as Seocho's Seoripul Igloo and Seongdong's Ongi Nurriso, and they usually stay up until around mid-March before being packed away for the next year.

The rest of the warmth is edible. Convenience stores keep heated cabinets of canned coffee, honey citron tea and rice drinks by the counter, and many sell baked sweet potatoes from a small roaster; our Korean convenience store food guide covers what else is worth picking up. And when a day of walking has gone fully into your bones, the warm floors of a jjimjilbang in winter are the Korean answer.

What to Pack and What to Buy When You Land

The simplest winter packing plan for Korea is to bring the things that need to fit you and buy the things that are cheap and everywhere.

Pack from home:

• Gloves you can use with a phone screen, since you will be checking maps and subway apps outdoors.
• A warm hat or earmuffs, and a scarf or neck warmer for windy days.
• Thick socks, and shoes you have already walked in for a full day.
• One or two thin thermal tops if you own them, to wear under everything else.
• A rechargeable hand warmer, if you have one, in your cabin bag rather than your suitcase.

Buy after you land:

• Disposable hot packs, pocket and stick-on types, plus insole warmers if you plan long walks. The Daiso Korea winter aisle is one of the easiest places to stock up.
• Extra thermal innerwear, if you find you need more layers than you packed.
• A long padded coat, if you would rather not carry one across the world.

Dry, heated indoor air comes with a Korean winter too, so a small tube of hand cream often rides in the same coat pocket as the hot packs; our Korean hand cream guide covers the options.

One thing to check before you fly is your airline's rule on hot packs. Disposable air-activated warmers are generally allowed by aviation security agencies such as Canada's CATSA, but policies on checked bags can vary by airline and airport, and many travelers are asked to keep them in their carry-on. Rechargeable warmers fall under lithium battery rules, which in Korea mean cabin bag only, never checked luggage. Since disposable packs are so easy to find on arrival, the least complicated choice is to buy them in Korea and use them up before you fly home.