SIM cards, eSIM and pocket Wi-Fi

If you travel alone and your phone supports it, an eSIM is the easiest option, while a physical SIM suits phones without eSIM. For groups sharing data, a pocket Wi-Fi can be economical. However, you have to carry and charge the device, and anyone who splits from the group loses the connection.

An eSIM lets you download a mobile plan with a QR code or app, without a physical card. Buy and install it online before you leave, then simply switch on that line when you land in Korea. Your phone must support eSIM and be unlocked from your carrier, so check both in advance.

Data-only plans give you internet access but no Korean phone number. Plans with a number let you make and receive calls and texts on a Korean number, which helps with taxi apps, deliveries and verification codes. Prepaid SIMs for tourists require identity checks with a passport or similar ID, and with some carriers calls and texts work only after your arrival is confirmed.

You can buy and activate one at telecom counters in the Incheon arrivals hall, or reserve online and pick it up at the airport. Some city telecom stores and convenience stores also sell prepaid SIMs. Airport lines can be long at busy times, so reserving ahead saves time.

Korea's three main carriers are SK Telecom, KT and LG U+, and many budget mobile operators resell their networks. All three offer good coverage across most of the country and in the subway. As a traveler, choose based on data amount, duration and whether you need a phone number rather than the carrier itself.

Many unlimited plans slow your speed after you use a certain amount each day. Messaging and maps usually still work at the reduced speed, but video may be sluggish. Before buying, check how much high-speed data is included and what the throttled speed will be.

Usually you reserve online, pick it up at an airport counter and return it at the airport when you leave. It comes with a charger and cable, so keep track of them. Late returns or losses can result in extra charges, so read the rental conditions.

A phone locked to your home carrier may not work with a Korean SIM or eSIM. Ask your carrier to unlock it before you travel, or check the lock status in your settings. If unlocking is not possible, use a pocket Wi-Fi or international roaming instead.

Roaming lets you keep your home number, but it is often expensive or comes with limited data. A Korean SIM or eSIM uses the local network directly and is often better on speed and price. If you need to receive verification texts on your home number, a dual-SIM phone lets you use both.

If you only use maps and messaging apps, data alone is enough. However, some taxi apps, delivery apps, restaurant bookings and shopping sites require text verification with a Korean number. If you plan to use those services, choose a plan that includes a phone number.

Korea has extensive mobile networks, so service works smoothly in most cities and even inside subway trains. Signals can be weak deep in the mountains, on some islands and in remote areas. If you are hiking or visiting islands, save offline maps beforehand.

Keep your home SIM in a small envelope or case so you do not lose it. Bring the SIM ejector pin too, so you can swap back easily when you go home. With an eSIM, your original SIM stays in the phone, so there is nothing to lose.

First check in your phone's settings that data is enabled for that line and that data roaming is switched on. Some plans require you to enter APN settings manually, so follow the seller's instructions. If it still fails, restart the phone and contact the seller's customer support.

Many prepaid plans let you add data or extend the period through an app, website or convenience store. With eSIMs, you often buy an add-on from the same seller. Choosing a plan with a little extra margin beyond your trip length saves the hassle of topping up.

If your child needs their own phone for maps or staying in touch, they will need a separate plan. For short trips, sharing a parent's phone hotspot can be enough. In case you get separated, give your child a note with your phone number and hotel address.

Most SIM and eSIM plans let you share data with other devices through your phone's hotspot. Some plans restrict tethering, and sharing uses up data faster, so check the conditions. If you will work on a laptop a lot, choose a plan with plenty of data.

Most people in Korea use KakaoTalk for messaging. Guesthouses, tour operators and shops often communicate through it, so installing it is helpful. Sign-up requires phone number verification, and you can register with an overseas number. Even guesthouse hosts often use it to contact guests.

At an airport counter, passport checks and setup usually take from a few minutes to a few tens of minutes. An eSIM installed in advance works as soon as you arrive. Plans with a phone number may take a bit longer than data-only plans because of identity verification.

Contact your SIM seller or carrier to suspend the line, and report the loss through the Police Civil Service 24 portal or at a nearby police station. As of November 2026, police lost-and-found reporting and searches are handled through that portal. Turning on your phone's find-my-device feature in advance helps, and get a copy of the report for any insurance claim.

Decide based on your trip length, daily data use, whether you need a phone number and whether your phone supports eSIM. Compare conditions across several sellers and read reviews. The key is choosing a plan that fits your itinerary rather than sticking to one brand.