Getting verification texts on your home number in Korea — should your home SIM stay on?

Do you need to keep your home SIM on to get verification texts?

Yes. Kedanto's Korea eSIM carries data and nothing else. It has no phone number and can't receive SMS, which leaves your home number as the only place your bank's or card issuer's one-time codes can land. That leaves one setup for your time in Korea: keep your home line on, route your internet through the Korea eSIM, and turn off data roaming on your home line. The comparison below is based on Apple and Samsung support pages as of 19 September 2026.

With both lines on, which number do the codes arrive on?

They arrive on the home number your bank has on file. Having two lines doesn't mean you need to choose anything to receive texts. Apple says that with Dual SIM, both phone numbers can make and receive voice and FaceTime calls and send and receive messages using iMessage, SMS and MMS. What it limits is data: your iPhone can use one cellular data network at a time.

Samsung describes the same thing from its side. Its Gulf support page (updated 15 June 2026) says Dual Standby keeps both SIMs active, but only one can receive a call at a time. On a Galaxy, the Messages choice in SIM manager is described by Samsung Korea as the SIM used "when sending new text and multimedia messages." Kedanto's eSIM has no number at all, so no setting can send a verification text to it.

What should you pick when your iPhone shows "Turn On Travel eSIM" in Korea?

If you want codes on your home number, it's Travel eSIM and Current eSIM. On an iPhone with iOS 26, tapping that notification offers two choices, Travel eSIM Only and Travel eSIM and Current eSIM. For verification texts, the difference comes down to whether your home line stays alive. Apple's page on using eSIM abroad says that if you keep both lines on, the capabilities on your primary line continue to work; for the travel-eSIM-only choice, the only things it names as carrying on over your home line are FaceTime and iMessage. Text verification is not one of them.

If the notification never showed up or you dismissed it, go to Settings › Cellular, make sure Turn On this Line is on for your home line, and pick the Korea eSIM under Cellular Data.

Why turn off data roaming on your home line?

To close off the route by which your home plan could carry your internet traffic. The switch is about internet access, and turning it off doesn't switch the line off. Apple describes Data Roaming as what lets a phone get online over cellular data outside its own carrier's network, not as a switch for whether texts arrive. The Dual SIM section of the iPhone User Guide says you may incur roaming charges if Data Roaming is on and you're outside the country or region covered by the carrier's network.

• iPhone: Settings › Cellular › your home number › Cellular Data Options › Data Roaming, set to off. Apple's instructions have Cellular Data turned on before you tap the number. Turn On this Line, which switches the whole line on or off, is a separate setting.
• Galaxy: Samsung UK's page (updated 5 June 2026) gives a single Data Roaming path, Settings › Connections › Mobile Networks › Data Roaming, with no step for choosing it per SIM. The SIM your phone uses for the internet is set in Settings › Connections › SIM manager, under mobile data; pick the Korea eSIM there.

Data roaming does need to be on for the Korea eSIM, or it won't connect. That path, and what to check if it still won't work, is in When your Korea eSIM is switched on but the internet isn't.

Which line should be the default for calls and texts?

Calls and texts on your home number, internet on the Korea eSIM. Apple describes your default number as the one used when you call or message someone who isn't in your Contacts app, and says that if you choose one number for cellular data only, the other becomes your default. Kedanto's eSIM has no number, so it is the data-only one. To change it after setup, go to Settings › Cellular › Default Voice Line and choose your home line.

On a Galaxy, Samsung Korea's guide has you open Settings › Connections › SIM manager and choose a SIM for calls, messages and mobile data separately. Set calls and messages to your home SIM and mobile data to the Korea eSIM. How these choices appear during installation is shown side by side in iPhone vs Galaxy: where the eSIM setup screens differ.

Will you be charged for codes sent to your home number?

That depends on your home carrier, so we can't give one answer here; ask them before you leave. Apple, too, notes when describing sending messages from either number that additional fees might apply and that you should check with your carrier. Four questions cover it:

• Is there a charge for receiving texts abroad, and if so, how much?
• Does international roaming need to be enabled on my account to receive texts abroad?
• Can data roaming be blocked on the account while calls and texts keep working?
• Can I use Wi-Fi calling abroad, and do texts come through when I do?

Why don't picture messages or visual voicemail come through?

Because Apple says that when data roaming is on for the number that uses cellular data, MMS and Visual Voicemail are disabled on your voice-only number. Apple's wording is: "If data roaming is on for the number that uses cellular data, then your voice-only number will disable Visual Voicemail and MMS." Kedanto's Korea eSIM is used in Korea with data roaming on, so in this setup your home number is the voice-only one. Apple lists those two features, MMS and Visual Voicemail, and regular SMS is not on that list.

It also works the other way. The iPhone User Guide says you may incur additional charges if you send SMS/MMS attachments on the line that's not selected for cellular data. We found no equivalent statement for Galaxy phones in Samsung's official pages.

Why do your maps stop while you're on a call on your home number?

Both SIMs wait for calls together, but once a call starts on one, the other rests, so data on the Korea eSIM can stop while you talk on your home number. Samsung Korea explains that Galaxy dual SIM uses DSDS (Dual SIM Dual Standby): when a call connects on one SIM, the other is deactivated and its calls and data are cut off, then it comes back when the call ends.

Apple says that if Allow Cellular Data Switching is off and you're on a call on a voice-only number that isn't your cellular data number, cellular data won't work during the call, and adds that this switching won't work if you're currently using Data Roaming. If you need maps or a translation app while taking a call from your card issuer, stay on hotel or café Wi-Fi. How to set Allow Cellular Data Switching is covered in iPhone vs Galaxy: where the eSIM setup screens differ.

How can you tell that both lines are alive?

If you see two signal-strength indicators at the top of the screen, both lines are on. Apple says the icons in the status bar show the signal strength of your two carriers and that you can see more status icons in Control Center. Samsung Korea likewise says two signal icons appear in the status bar when both a physical SIM and an eSIM are in use. If one signal disappears, check Turn On this Line for that line under Settings › Cellular on iPhone, or that SIM's switch in SIM manager on Galaxy.

Before you fly, put the four questions above to your home carrier, and finish signing up and verifying the apps you'll use in Korea while you're still at home. Which apps accept a home number is in What works in Korea without a Korean phone number, and whether to take your home SIM out at the airport is in Incheon Airport SIM vs Korea eSIM.

Say you're booking concert tickets from your Seoul hotel with your home card and a box appears asking for a verification code. If your card issuer sends codes by text, it will be waiting in the thread on your home number: the booking page loaded over the Korea eSIM, and the code came in over your home line.