Short answer
Apple, Google, and Samsung document a second line beside your home number on the models they list, and each lets you choose which line carries cellular data. On the iOS 26 prompt that keeps both lines, Apple says you might still incur roaming fees from the home eSIM.
A Japanese phone number, cellular calls, SMS, and what LINE, WhatsApp, FaceTime, and iMessage do with a number are covered in Do I get a Japanese phone number with a Japan eSIM?.
Fact table
As of 2026-10-20
Each claim names its source. The full source list, with the date each page was read, is below.
| Claim | Source |
|---|---|
| On supported iPhone models, Apple says you can have two eSIMs active at the same time, one for your home phone number and another for the place you are visiting. If the iPhone has a SIM tray, you can use a physical SIM and an eSIM while traveling internationally. That page requires an iPhone XS, iPhone XS Max, iPhone XR, or later. | Apple Support, travel with eSIM |
| Apple says that while you are abroad you can use a travel eSIM by itself or keep both lines on. If both stay on, the capabilities on the primary line continue. On the iOS 26 prompt that uses both lines, the travel eSIM is used for data, and Apple says you might still incur roaming fees from the home eSIM. | Apple Support, travel with eSIM |
| Apple says you choose the data line in Settings, under Cellular, then Cellular Data. | Apple Support, travel with eSIM |
| Apple says Dual SIM is two active phone numbers for calls and text messages, and that the iPhone uses one cellular data network at a time. iPhone 13 models and later can use two eSIMs as well as a physical SIM and an eSIM. To use two carriers, the carrier must unlock the iPhone, or both plans must be from the same carrier. | Apple Support, Dual SIM with an eSIM |
| Apple says both phone numbers can make and receive voice calls and can send and receive SMS and MMS. You choose a default number for someone who is not in Contacts, and you choose which plans to use for iMessage and FaceTime: either number, or both. | Apple Support, Dual SIM with an eSIM |
| Apple says that during a call you can answer the other number if that carrier supports Wi-Fi calling. If you are on the line that is not the cellular-data line, Allow Cellular Data Switching has to be on to receive calls on the other line. Otherwise the incoming call goes to voicemail if voicemail is set up, and you do not get a missed-call notification from the secondary number. Apple says this data switching will not work while you are using Data Roaming. | Apple Support, Dual SIM with an eSIM |
| Apple says that if Data Roaming is on for the number that uses cellular data, the voice-only number disables Visual Voicemail and MMS. | Apple Support, Dual SIM with an eSIM |
| Apple says Data Roaming permits internet access over a cellular data network in regions the carrier network does not cover, and that a carrier might include international roaming on some plans without additional fees. To avoid fees and higher rates, Apple says to contact the carrier before you go. | Apple Support, cellular data roaming |
| On Dual SIM, Apple says you turn on Cellular Data, tap the number you want to modify, open Cellular Data Options, and turn on Data Roaming plus the other settings that carrier suggests. The same page says Data Roaming can be turned off under Cellular Data Options. | Apple Support, cellular data roaming |
| Apple says Wi-Fi Calling makes and receives voice calls over Wi-Fi where cellular coverage is low or absent. With more than one SIM, you scroll to the line and turn Wi-Fi Calling on for that line. If it will not turn on, Apple says to verify that Wi-Fi Calling is available from the carrier. | Apple Support, Wi-Fi Calling |
| Google says a Pixel 3a or later can use one physical SIM and one eSIM, called Dual SIM Dual Standby, and that you choose which SIM is used for calls, texts, and data. Only one SIM can be the default for data. A Pixel 7 or later can use two eSIM profiles at once if the carrier allows it. A Pixel 3a bought in Japan cannot have two SIMs. In the US, a Pixel 10 or later, except the Pixel 10 Pro Fold, can only use an eSIM. Google says the steps for those defaults are for Android 11 and up, and that you ask the carrier whether dual SIM will work on your phone. | Google Pixel Help, dual SIMs |
| On Pixel 8, Pixel 8 Pro, and earlier, Google says you cannot receive a call on the other SIM during a call, and those calls go to voicemail. On Pixel 8a and later, Google says both SIMs can handle calls at the same time if mobile data is on for both, automatic data switching is on, and the carrier for the second SIM supports Wi-Fi calling; the first call goes on hold. Google says you can turn a SIM off temporarily with Use this SIM. | Google Pixel Help, dual SIMs |
| Google says Roaming lets the phone send data over other carrier networks when you leave an area the carrier covers. On a phone with more than one SIM, Google says you change the mobile-network information for each SIM from the tabs at the top of mobile network settings. | Google Pixel Help, mobile networks |
| Google says some carriers charge extra for data roaming, and that on a Pixel you turn Roaming on or off under Settings, Network and internet, then SIMs. | Google Pixel Help, mobile data usage |
| Samsung says an eSIM can be used alongside a physical SIM to add a second phone number or carrier. In SIM manager you can enable or disable each connection, and Primary SIM changes the default for calls, texts, and data. The Phone app can switch between the physical SIM and the eSIM for a call, and the Messages app can select the SIM for a conversation. Samsung says the screens may vary by carrier, software, and model, and that some carriers may not support the eSIM. | Samsung, SIM cards |
| Samsung lists hybrid eSIM dual SIM, a physical SIM plus an eSIM, for the Galaxy S20 through S26 series, the Note 20 series, named Z Fold, Z Flip, and Z TriFold models, the XCover6 Pro, and named Galaxy A and Tab models. Samsung says only devices unlocked by Samsung can support Dual Physical SIM. | Samsung, SIM cards |
| Samsung Australia says a compatible Australian-variant Galaxy supports one nano-SIM and one eSIM. Preferred SIM card is where you specify which SIM to use for a feature such as voice calls when two cards are on. Auto data switching uses the other SIM for data if the preferred SIM cannot connect. Samsung Australia says the menus may vary by model and software. | Samsung Australia, nano-SIM and eSIM |
FAQ
Will I keep my home number on a Japan trip?
On the iPhone models Apple lists, you can keep your home number on one line and use another eSIM for the place you are visiting, or a physical SIM beside an eSIM if the phone has a SIM tray. If both lines stay on, Apple says the capabilities on the primary line continue. Pixel and Galaxy phones can keep a second line on the models Google and Samsung list.
Can my home line and a travel eSIM be on at the same time?
Apple says a supported iPhone can have two eSIMs active, and it uses one cellular data network at a time. Google calls the Pixel arrangement Dual SIM Dual Standby, and you can turn a SIM off with Use this SIM. Samsung SIM manager has a switch for each connection.
Which line should I set for data?
Apple says you choose it under Settings, Cellular, then Cellular Data. When the iOS 26 prompt keeps both lines, Apple says the travel eSIM is used for data. Google says only one SIM can be the default for data. On the Samsung US page, Primary SIM is the default for calls, texts, and data.
Does choosing that data line avoid home-carrier roaming fees?
Apple says you might still incur roaming fees from the home eSIM when the iOS 26 prompt keeps both lines. To avoid fees and higher rates, Apple says to contact the carrier before you go. Google says some carriers charge extra for data roaming.
Will calls and texts still reach my home number?
Apple says both numbers can make and receive voice calls and can send and receive SMS and MMS. During a call, answering the other number depends on Wi-Fi calling from that carrier, and without it the call goes to voicemail with no missed-call notification from the secondary number. On Pixel 8, Pixel 8 Pro, and earlier, Google says calls to the other SIM go to voicemail while you are on a call.
Will a bank or sign-in text still reach my home number?
Apple says both numbers can send and receive SMS and MMS, and Google lets you choose which SIM is used for texts. Apple says to contact the carrier about international roaming and whether additional fees apply.
Can I use Wi-Fi Calling with my home number?
Apple says Wi-Fi Calling makes and receives voice calls over Wi-Fi where cellular coverage is low or absent, and you turn it on for one line when the iPhone has more than one SIM. If it will not turn on, Apple says to verify that Wi-Fi Calling is available from the carrier. On Pixel 8a and later, Google says calls on both SIMs at the same time require the carrier for the second SIM to support Wi-Fi calling.
Does the phone have to be unlocked?
Apple says that to use two carriers, the carrier must unlock the iPhone, or both plans must be from the same carrier.
Sources
Apple Support, travel with eSIMsupport.apple.com
Two eSIMs can be active on supported iPhone models, one for a home number and one for the place you are visiting. A SIM tray can hold a physical SIM beside an eSIM. Keeping both lines on leaves the primary line working, and the iOS 26 both-lines prompt uses the travel eSIM for data while roaming fees from the home eSIM may still apply. The data line is chosen under Settings, Cellular, Cellular Data.
Accessed 2026-10-20.
Apple Support, Dual SIM with an eSIMsupport.apple.com
Dual SIM is two active numbers for calls and texts, on one cellular data network at a time. iPhone 13 and later can use two eSIMs. Two carriers require an unlock, or both plans from the same carrier. Both numbers can use voice, SMS, and MMS. Wi-Fi calling on the other line matters during a call. Data switching does not work while Data Roaming is in use. Data Roaming on the data number disables Visual Voicemail and MMS on the voice-only number.
Accessed 2026-10-20.
Apple Support, cellular data roamingsupport.apple.com
Data Roaming is internet access outside the carrier network. Some plans may include international roaming without additional fees. Contact the carrier before you go to avoid fees and higher rates. On Dual SIM, Data Roaming is turned on per number under Cellular Data Options, and Data Roaming can be turned off there.
Accessed 2026-10-20.
Apple Support, Wi-Fi Callingsupport.apple.com
Wi-Fi Calling makes and receives voice calls over Wi-Fi where cellular coverage is low or absent. With multiple SIMs, it is turned on for the line you select. If it will not turn on, verify that the carrier offers it.
Accessed 2026-10-20.
Google Pixel Help, dual SIMssupport.google.com
Pixel 3a and later can use one physical SIM and one eSIM (Dual SIM Dual Standby), with separate choices for calls, texts, and data, and only one data SIM. Pixel 7 and later can use two eSIMs if the carrier allows. A Pixel 3a bought in Japan cannot have two SIMs. In the US, Pixel 10 and later, except Pixel 10 Pro Fold, are eSIM only. Call handling differs for Pixel 8 and earlier versus Pixel 8a and later. A SIM can be turned off.
Accessed 2026-10-20.
Google Pixel Help, mobile networkssupport.google.com
Roaming lets the phone send data on other carrier networks outside the home carrier coverage. With more than one SIM, mobile-network settings for each SIM are on the tabs at the top of mobile network settings.
Accessed 2026-10-20.
Google Pixel Help, mobile data usagesupport.google.com
Some carriers charge extra for data roaming. On a Pixel, Roaming is turned on or off under Settings, Network and internet, then SIMs.
Accessed 2026-10-20.
Samsung, SIM cardssamsung.com
An eSIM can sit beside a physical SIM as a second number. SIM manager enables each line, and Primary SIM is the default for calls, texts, and data. The Phone and Messages apps can switch the SIM for one call or conversation. The page lists the hybrid eSIM models and says only a Samsung-unlocked device can support Dual Physical SIM. Screens vary by carrier, software, and model.
Accessed 2026-10-20.
Samsung Australia, nano-SIM and eSIMsamsung.com
A compatible Australian-variant Galaxy supports one nano-SIM and one eSIM. Preferred SIM card picks the SIM for a feature such as voice calls, and Auto data switching moves data to the other SIM when the preferred SIM cannot connect. Menus vary by model and software.
Accessed 2026-10-20.