International plans from U.S. providers are not practical for retiree's in Korea

International plans from U.S. providers are not practical in Korea. There is no AT&T, no Verizon etc and unless you have some special (expensive) plan with those stateside providers for roaming services, you will want to get a Korea number. Most bases in Korea already have a concession in the AAFES Exchanges where you can do this.

NOTE: If you have a Korea ARC card (Alien Registration Card) bring it, as you can, and should, use it vs your DOD ID Number. There are definitely benefits to staying on base to get a phone, but just because it’s the easiest, doesn’t mean it makes the most sense for everyone. There are plenty of off-base locations throughout the country, but if you do go this route, you might consider bringing someone who can speak Korean.

  "Can I use my U.S. phone in Korea?"  Yes via Pre-paid short-term or Post-paid long-term plans.

Pre-Paid SIM Cards in Korea - for SHORT-TERM Plans

To use a pre-paid plan, users must purchase a pre-paid SIM cards and credits in advance, which are pay-as-you-go cards that you add money to for minutes. They are readily available downtown, at the airport, convenient stores etc. There are also SIM cards you can purchase for a specific length of time i.e. a 30-day card that expires in a month and is then a throw-away. All this allows people to use their own phones and add a SIM card to it.

You cannot however, purchase a phone separately and then add a SIM card expecting a long-term plan. You need a contract for that. If you absolutely want to use your current unlocked phone, you can go downtown and get a prepaid SIM, but it's a bad idea IMHO if you are looking long-term.

Post-Paid Service Contracts in Korea - for LONG-TERM Plans

If you intent to remain in Korea a long time, it is advisable to sign up for a service plan by Contract. Each company has numerous plans, but to be honest any of the unlimited plans are very cost effective and well worth it. They also do have Non-contract plans, which is a monthly payment plan and allows you to use your stateside unlocked phone. They provide a SIM, set up the payment plan for the service and you pay monthly. There is no discount doing it this way vs a 1-2 year contract have discounts.

In order to get a long-term plan, you need to sign up for a 1-2-year contract. These can include a phone or not. Once you have a plan you can then purchase new phones anywhere and swap your SIM into it and have the same services. I have had the same unlimited plan for years and years, going through a lot of phones over the years dating back to before my Samsung S3.

If you choose to do this, which I highly recommend, DO IT ON-BASE at the Exchange. The services provided on-base are not base services! They are concessions of the Exchange of the Korean companies, all the Korean companies, and are in fact Korea contracts same as you get if you do it downtown. So why do I say do it on-base? Convenience pure and simple. No language barriers. Customer service representatives who are used to working with the U.S. military communities and our customs and courtesies. And they are right at the Exchange. It's just simple. Downtown is of course a good option, but be aware of the benefits I just mentioned that you may not get downtown.

Your Korea Phone Number Becomes Your ID

Your phone number becomes like a personal ID number for many other Korea-based programs and applications, and allows you to access nearly all of the services available in South Korea such as banking, paying for goods, travel and much more. Your phone number becomes how you verify your identity for nearly everything. So, ensuring a person’s phone number is set up correctly is very important, and changing your number may cause you many large hassles. So choosing the correct provider is important. In Korea, there are three main providers: SK Telecom, LG U+ and Korea Telecom (KT).

  "Can change cell phones but keep the same phone number?"

YES.  When/If you change your cell phone (age, broken, just want a new one), you just swap your current SIM into your new phone. You do not need to purchase a new plan or phone number when you change equipment. However, you cannot do this on-base! The on-base Exchange concessions only sell plans, which come with phones, but they do not sell phones by themselves. You must go downtown to purchase a phone without a plan.

Korea Telecommunications Company Services

As mentioned above, Korea still offers pay-as-you-go (prepaid) SIM cards that you can use in your existing phone. But the more common method is a smartphone contract, which can be 1-2 years normally, and includes the phone as part of the price. As mentioned, there are three primary service providers

SK Telecom operates several authorized stores with signs that say ‘T World’ or ‘SK (Telecom)’ as well as a customer call center exclusively for foreigners. Please call the customer center beforehand in order to find out which stores provide interpretation services, since not all of them do.

KT operates three service centers throughout Seoul and a customer call center exclusively for foreigners. The most representative KT center, located in Gwanghwamun, provides mobile phone subscription manuals in foreign languages. Moreover, in partnership with the volunteer translation service organization, BBB Korea, the Gwanghwamun service center offers consultation in 17 different languages.

KT Telecom Contract and Non-contract Plans as of Feb 2024

Formerly known as LG Telecom, LG U+ is owned by the LG Corporation. The company is known for its G series of smartphones as well as a variety of other electronics including TVs. With roughly 20% of the market, the No. 3 mobile service in Korea trails its two main rivals.

LG U+ Contract and Non-contract Plans as of Feb 2024

Where To Buy

Choose the cell phone shop carefully. Again, on-base services help take some of the worry out of the process. Other than on-base, there are two main types of shops: Primary and Secondary retailers. Choosing a primary retailer means the store is owned and managed by the telecom company you chose to contract with. Secondary retailers may charge additional fees, may cell used-as-new phones, and often do not fully understand the contracts. As mentioned, using the on-base AAFES concessions is always a wise choice.

Useful Cell Phone Apps

• Kakao Talk: Kakao Talk is available on all platforms of smartphones and PC. It is used by practically all Korean people. It is an application that allows you to message and even to call your friends for free when you have access to Wi-Fi. It is also a great way to stay in touch with people from your home country if you can get them to install it!
• Naver Map: Naver Map is an informative navigation app which provides information on transportation and facilities as well as navigation function. By using Naver Map, you can search the routes and transportation schedules. It also provides locations and detiled information on cafes, restaurants, pharmacies, banks and ATMs around you.
• KakaoMetro: KakaoMetro provides a metro map and searching services as you select your start and destination stations. It shows the detils of the route, metro schedules, estimated arrival time and transfer information.
• Naver Papago: Apart from the Google Translation, Naver Papago can be an one of the more accurate translation app. It has translation, AI translation and speech recognition functions, so that you can easily translate the words, sentences and voices.