How to Set Up Dual SIM and eSIM on Your Phone

Published 2026-10-16 · Marion Phone Repair

You want to use two phone numbers on one device — a personal number and a work number, a local number and a travel number, or two numbers from different carriers to get the best coverage and pricing. Modern phones support this through dual SIM, where the phone holds two SIM profiles simultaneously. The two main methods are a physical nano-SIM card paired with an eSIM (embedded SIM), or on newer phones, two eSIMs with no physical card at all.

Understand the options

Physical SIM + eSIM: Your phone has one nano-SIM slot and one built-in eSIM chip. You put one carrier's physical SIM in the tray and activate the second carrier's eSIM digitally. This is the most common dual SIM setup on iPhones (iPhone XS and later) and most modern Android flagships
Dual eSIM: Newer phones (iPhone 13 and later, Samsung Galaxy S23 and later, Google Pixel 7 and later) support two eSIM profiles simultaneously with no physical SIM card needed. iPhone 14 and later models sold in the US have no physical SIM tray at all — they are eSIM only
Dual physical SIM: Some Android phones (common in markets outside the US) have two nano-SIM card slots. Each slot holds a physical card from a different carrier. This is becoming less common on flagship phones but is still standard on many mid-range Android devices

Set up eSIM on iPhone

Get an eSIM from your carrier

Before you start, you need an eSIM activation from your carrier. There are several ways to get one:

eSIM Carrier Activation: Some carriers (AT&T, T-Mobile, Verizon in the US) support automatic eSIM activation. When you buy a new iPhone or add a line, the carrier pushes the eSIM profile to your phone automatically
QR code: Your carrier provides a QR code (on paper, in an email, or in their app) that contains the eSIM activation details. This is the most common method
Carrier app: Some carriers let you activate an eSIM directly through their app on your phone
Transfer from another phone: If you already have an eSIM on a previous phone, you can transfer it to your new phone during setup

Activate the eSIM

Go to Settings, Cellular (or Mobile Data in some regions)
Tap Add eSIM (or Add Cellular Plan on older iOS versions)
If your carrier supports eSIM Carrier Activation, it may appear automatically. Tap it to activate
If you have a QR code, tap Use QR Code and point your camera at the code. The phone reads the activation details and downloads the eSIM profile
If prompted, enter the confirmation code provided by your carrier
Choose a label for this line — Personal, Business, Travel, or a custom name. This label helps you identify which line is which throughout the phone's settings and when making calls
Choose your default line for voice calls, SMS, and data (more on this below)

Set up eSIM on Android

Samsung Galaxy

Go to Settings, Connections, SIM manager (or SIM card manager)
Tap Add eSIM
Scan the QR code from your carrier, or if your carrier appears in the list of supported carriers, select it and follow the on-screen activation
Once activated, the SIM manager shows both your physical SIM and the eSIM. Tap each one to rename it for easy identification

Google Pixel

Go to Settings, Network and internet, SIMs
Tap the plus icon or Add SIM
Choose Download a SIM instead if you are adding an eSIM (not inserting a physical card)
Scan the carrier QR code or enter the activation details manually
Follow the prompts to complete activation and label the line

Other Android phones

The path varies by manufacturer but generally follows: Settings, Network or Connections, SIM cards or SIM manager, Add eSIM. Look for options labeled Download SIM, Add mobile plan, or Add eSIM. If your phone does not show any eSIM option, it may not support eSIM — check your phone model's specifications to confirm.

Configure dual SIM defaults

Once both SIMs are active, your phone needs to know which line to use by default for different functions:

Default voice line

This is the number used when you make a phone call. You can set one line as the default for all calls, or set the phone to ask you which line to use before each call. On iPhone: Settings, Cellular, Default Voice Line. On Android: Settings, SIM manager, Preferred SIM for calls.

Default SMS line

The number used for sending text messages. Same location as the voice default. Some messaging apps also let you choose which line to use per conversation.

Default data line

Which SIM provides your mobile data connection. Only one SIM can provide data at a time — the other SIM stays active for calls and texts but does not use its own data plan. Choose the line with the better data plan or faster speeds. On iPhone: Settings, Cellular, Cellular Data. On Android: Settings, SIM manager, Mobile data.

Per-contact line assignment

Both iPhone and Android let you assign a specific SIM line to individual contacts. When you call or text that contact, the phone automatically uses the assigned line. This is useful for keeping work contacts on your work number and personal contacts on your personal number. On iPhone, open the contact, tap Preferred Cellular Plan, and select a line.

Common dual SIM use cases

Work and personal: Keep your work number separate from your personal number on one phone. You can silence the work line after hours using Focus modes (iPhone) or Do Not Disturb rules (Android) while keeping your personal line active
Travel: Keep your home carrier SIM for receiving calls and texts from people who have your regular number, and add a local eSIM in the country you are visiting for cheap local data. Carriers like Airalo, Holafly, and Ubigi sell travel eSIMs for nearly every country
Coverage: If you live or work in an area where one carrier has weak signal, use a second carrier for data while keeping your primary number on the first carrier for calls
Separate data plan: Some carriers offer data-only plans at lower rates. Use your primary SIM for calls and texts and a data-only eSIM from a cheaper carrier for mobile data

Troubleshooting dual SIM issues

One SIM shows No Service: Make sure both SIMs are enabled. Go to Settings, Cellular (iPhone) or SIM manager (Android) and verify each line is toggled on. Also check that the SIM's carrier has coverage in your area
Cannot receive calls on one line while on a call on the other: Most phones support DSDS (Dual SIM Dual Standby), not DSDA (Dual SIM Dual Active). In DSDS mode, when you are on a call on one line, the other line is temporarily unavailable. Callers to the second line will go to voicemail. iPhone 14 Pro and later and a few Android phones support DSDA, where both lines can receive calls simultaneously
Data not working after adding second SIM: Check which SIM is set as the default for data. Only one SIM handles data at a time. Also check that data roaming is enabled for the correct SIM if you are using a travel eSIM
iMessage or FaceTime registering on wrong number: Go to Settings, Messages, Send and Receive, and Settings, FaceTime, and check which phone number or email is selected for each service. You can choose which line iMessage and FaceTime use

eSIM and dual SIM help in Marion

If you need help setting up eSIM, configuring dual SIM defaults, transferring an eSIM to a new phone, or troubleshooting dual SIM issues, Marion Phone Repair can walk you through the setup, activate your eSIM, and configure your lines so calls, texts, and data all route correctly.