How to set up a second line on Android: eSIM, Dual SIM and hidden chips

Two phone lines on one smartphone are not a luxury, but a necessity for many users. Separate work and personal calls, take advantage of competitive rates from different operators, or support a local SIM while traveling—without having to carry two devices. But how to configure it correctly so as not to encounter problems like missing SMS or network conflicts? a second line on Android solves a lot of problems without having to carry two devices. But how to configure it correctly so as not to encounter problems like missing SMS or network conflicts?

In this article we will look at all the current ways to add a second line: from classic Dual SIM to modern eSIM, including hidden settings for models Samsung Galaxy, Google Pixel i Xiaomi. We’ll also find out why sometimes the second SIM doesn’t connect to the network and how to fix it without contacting a service center.

Spoiler: setup takes no more than 5 minutes if you know the nuances. For example, on some Xiaomi smartphones, the second line by default blocks mobile data for the first SIM - this can be corrected manually.

1. Checking compatibility: does your smartphone support a second line?

Before you try to add a second SIM card, make sure that your device allows it. There are three main scenarios:

• 📱 Dual SIM (DSDS) —two physical slots for nano-SIM. Supports most budget and mid-budget smartphones (for example, one slot for nano-SIM and virtual card support. Common in flagships (eSIM + physical SIM; combined slot (nano-SIM + microSD or second SIM). Found in older models ( Redmi Note 12, Samsung Galaxy A54).
• 📲 eSIM + physical SIM — one nano-SIM slot and virtual card support. Common in flagships (Google Pixel 8, iPhone 15, Samsung Galaxy S24).
• 🔄 Hybrid Dual SIM - combined slot (nano-SIM + microSD or second SIM). Found in older models (Samsung Galaxy S9, Huawei P30).

You can check support for the second line like this:

1. Open Settings → About phone → Specifications (path may vary).
2. Look for lines like Dual SIM, eSIM or Dual SIM cards.
3. If there is no information, enter the phone model in the search engine with the request Dual SIM support.

Important! On some devices (for example, Samsung Galaxy S22 Ultra) the second line only works in mode 4G/3G, even if the main supports 5G. This is a hardware limitation and cannot be circumvented.

⚠️ Attention: If your smartphone was released before 2019, check whether the operator blocks the use of a second SIM. For example, some versions of Huawei i Honor with Chinese firmware may have such a limitation.

2. Method 1: Adding a second physical SIM card

The easiest method is to use the second slot for nano-SIM. Suitable for most devices with Dual SIM.

Step-by-step guide:

1. Turn off the phone (Necessarily!). Remove the SIM card tray using a paper clip or a special key.
2. Place the second nano-SIM in the free slot. chip position —it should be pointing down.
3. Turn on the device. Wait for the notification about the new SIM card to appear.
4. Go to Settings → SIM cards and mobile networks (or a similar section).
5. Click on the second SIM and configure:
   • 📞 Line name (for example, "Work").
   • 🌐 mobile data (select which SIM will be the main one for data).
   • 📞 Calls and SMS (you can set separate settings for each line).

If the second SIM is not detected:

• 🔄 Restart the phone.
• 📶 Check if the operator supports work in your region (for example, Tele2 may limit roaming for the second line).
• 🛠️ Clean the SIM card contacts with a dry cloth - sometimes oxidation interferes with reading.

⚠️ Attention: On some smartphones Xiaomi (for example, Redmi Note 10 Pro) by default the second SIM disables mobile data for the first. To fix this, go to Settings → SIM cards and mobile networks → Data switching and select Auto or Basic SIM.

3. Method 2: Setting up an eSIM (virtual SIM card)

eSIM is a built-in SIM card that does not need to be physically inserted into the phone. It's ideal for a second line, especially if you travel frequently or want to save slot space. However, not all operators and smartphones support this technology.

Which phones support eSIM?

Brand	Supported models (2022–2026)	Features
Google	Pixel 6/7/8, Pixel Fold	Supports multiple eSIMs at the same time
Samsung	Galaxy S21/S22/S23/S24, Z Flip/Fold 3/4/5	On some models, eSIM works only with certain operators
Apple	iPhone SE (2022), 14/13/15 series	Not officially sold in Russia, but eSIM works on “gray” ones models
Xiaomi	12T Pro, 13 Pro, Mix Fold 2/3	Requires the latest version of MIUI

How to activate eSIM?

The process depends on the operator, but the general scheme is as follows:

1. Make sure that your phone supports eSIM (see table above).
2. Contact the operator for QR activation code or data for manual entry. For example:
   • MTS and Beeline issue QR through your personal account.
   • MegaFon requires salon visits.
   • Tele2 supports eSIM only for corporate clients.

Go to Settings → Mobile network → Add mobile tariff → Add using a QR code.

Scan the QR or enter the data manually (if the operator has provided SMDP+ Address and Activation code).

Wait for activation (may take up to 10 minutes).

What to do if the eSIM does not activate?

If after scanning the QR code the error “Could not connect to the activation server” appears, try:

1. Connect to Wi-Fi (mobile data may be blocked by your operator).

2. Reboot the phone.

3. Make sure that the date and time on the device are set automatically.

4. Contact your operator's support - sometimes you need to link the eSIM to the phone's IMEI.

Advantages of eSIM:

• ✅ No need for a physical card - you can quickly switch between tariffs.
• ✅ Ideal for traveling (for example, buying a local SIM through Airalo or Holafly).
• ✅ You can have up to 5-8 eSIM profiles (depending on the phone model).

Disadvantages:

• ❌ Not all operators support eSIM (especially regional ones).
• ❌ It is more difficult to transfer to another phone (re-activation is required).
• ❌ On some smartphones, eSIM does not work with 5G.

4. Setting priorities: how to manage two lines?

After adding a second line, you need to configure which one will be used by default for calls, SMS and mobile data. menu SIM card settings, but the interface may differ.

Basic settings:

• 📞 Calls:
  • Select which SIM will be used for outgoing calls by default.
  • On some phones (for example, Samsung), you can set rules: for example, calls to numbers with a code +7 through the first SIM, and to +375 through the second.
• 💬 SMS:
  • Similar to calls, select SIM for outgoing messages.
  • On Google Pixel you can configure automatic switching to the second SIM if the first one does not catch the network.
• 🌐 mobile data:
  • Select the main SIM for data transfer. On some phones you can enable Automatic switching, if the main network disappears.
  • On Xiaomi in the menu Settings → SIM cards → Data switching you can enable the option Use both SIMs for the Internet (but this will increase battery consumption).

Example of setting on Samsung Galaxy S24:

Settings → Connections → SIM card manager → Select SIM for calls/SMS/Internet

How to find out which SIM is used for a call?

On most smartphones next to the indicator network, the SIM name is displayed (for example, "Personal" or "Work"). If this is inconvenient, you can:

• 🔄 Assign different colors for each SIM (available on MIUI i One UI).
• 📱 Install an application like Dual SIM Selector for quick switching.
• 📞 In some firmware (for example, ColorOS on Oppo/Realme) when an outgoing call, a window appears with the choice of SIM.

5. Common problems and their solutions.

Even after proper configuration, the second line may malfunction. Here are the most common problems and ways to fix them:

Problem 1: The second SIM does not catch the network

Possible causes and solutions:

• 📶 No operator coverage: Check the coverage area on the operator's website. For example, Tele2 may not work in remote areas.
• ⚙️ Incorrect APN settings: Go to Settings → Mobile network → Access points (APN) and select your operator's profile. If it is not there, add it manually (the data can be found on the operator’s website).
• 🔋 Battery saving: On some phones (for example, Huawei) in To save energy, the second SIM is disabled. Check your battery settings.
• 📱 Hardware malfunction: If the slot is damaged, the SIM will not be detected. Try inserting it into another phone to check.

Problem 2: SMS do not arrive on the second SIM

Most often this is due to:

• 📥 Blocking messages: Check whether the spam filter is activated in application Messages.
• 📵 Lack of registration on the network: Go to Settings → Mobile network → Access point names and select the correct profile.
• 🔄 Conflict with applications: Some banking applications (for example SberBank Online) can block SMS for the second SIM. Try temporarily disabling such apps.

Problem 3: The battery drains quickly

Two active SIM cards increase battery consumption as the phone is constantly scanning two networks. To reduce consumption:

• 🔋 Disable 4G/5G for the second SIM if it is used only for calls: Settings → Mobile network → Preferred network type → select 3G.
• 📵 Turn on the mode On the plane for the second SIM at night (if it is not needed).
• 🔄 Use the function Intelligent switching (available on Samsung i Google Pixel) so that the phone automatically turned off the second SIM when the battery was low.

⚠️ Attention: On some smartphones Realme and Oppo when the second SIM is activated, support is automatically disabled VoLTE (4G calls) for both lines. To return VoLTE, you may need to manually configure IMS.

6. Hidden tricks: how to maximize the benefits of a second line

A second SIM card can be more useful than it seems at first glance. Here are some life hacks:

1. Separation of work and personal contacts

On phones with MIUI (for example, Xiaomi 13) and One UI (Samsung) you can:

• 📇 Link contacts to a specific SIM. For example, all work numbers will call only to the second line.
• 🔍 Use separate black lists for each SIM.
• 📊 Enable call statistics for each line (useful for cost control).

2. Saving on roaming

If you often travel abroad:

• 🌍 Buy a local SIM or eSIM (for example, through Airalo) and use it only for the Internet, and the main one for calls.
• 📶 Configure automatic switching to the local network: on Google Pixel this is done in Settings → Network and Internet → SIM cards → Automatic network selection.
• 💰 Use applications like Dent to purchase temporary traffic packages by favorable prices.

3. Security and confidentiality

The second line will help:

• 🔒 Register in services under a “clean” number (for example, for sales on Avito or Yule).
• 📱 Use one SIM for banking applications, and the second for social networks (reduces the risk of data leakage).
• 🔄 Quickly change the number if the main one is blocked (for example, due to spam).

How to hide the second line from applications?

Some applications (for example, WhatsApp or Viber) may request access to all SIM cards. To limit this:

1. Go to Settings → Applications → Permissions → Phone.

2. For unnecessary applications, disable access to Reading information about SIM cards.

3. On Android 13+ you can create a separate user profile with limited rights for the second SIM.

7. Comparison of methods: which second line is better?

The choice between physical SIM and eSIM depends on your tasks. Here is a comparison table:

Criteria	Physical SIM	eSIM
Ease of installation	Requires a physical slot, risk of damaging the card	Activation in 2 minutes using a QR code
Operator support	Works with all operators	Not all operators support (for example, Tele2 only for corporate clients)
Travel	You need to buy a local SIM	You can buy an eSIM in advance (for example, through Nomad or Airalo)
Cost	Free (if there is a free slot)	Some operators charge an activation fee (for example, MegaFon — 100₽)
Transfer to another phone	Just move the card	Requires re-activation

When to choose a physical SIM?

• ✅ Your phone does not support eSIM.
• ✅ You often change devices.
• ✅ Your operator does not work with eSIM.

When to choose eSIM?

• ✅ You need a second line for travel.
• ✅ You want to save space in the slot (for example, for microSD).
• ✅ You use Google Pixel or iPhone (eSIM works there more stable).

FAQ: Frequently asked questions about the second line on Android

Is it possible to use two lines on a phone without Dual SIM?

Technically yes, but with limitations:

• 📱 Applications for the second line: Google Voice, Dingtone or TextNow allows you to make calls via the Internet, but this is not a full-fledged SIM.
• 📞 USB modems: Some devices (for example, Sony Xperia) support connecting an external modem via OTG, but this is inconvenient.
• ⚠️ Limitations: Without a physical or virtual SIM, you will not be able to receive SMS (important for banks and instant messengers).

Why does the second SIM not work after updating Android?

This is a common problem, especially on smartphones Xiaomi i Samsung. Reasons and solutions:

• 🔄 Reset network settings: Go to Settings → System → Reset → Reset mobile network.
• 📥 Operator firmware update: Check for updates in Settings → About phone → Software update.
• 🛠️ Manual APN setting: If automatic settings do not apply, add the APN manually (data can be obtained from the operator's website).

If all else fails, try removing and reinserting the SIM card.

Is it possible to make calls on one SIM and sit on the other? Internet?

Yes, but it depends on the phone and operator:

• 📱 Samsung Galaxy (One UI): Enable Allow calls during data transfer in the SIM settings.
• 📲 Google Pixel: Function Dual SIM Dual Standby (DSDS) allows you to use both SIMs at the same time.
• ❌ Xiaomi (MIUI): On most models, when the Internet is active on one SIM, the second one becomes unavailable for calls.

Also make sure that your operator supports VoLTE (4G calls), otherwise the Internet will be disconnected when making a call.

How to transfer a second line from one phone to another?

The method depends on the SIM type:

• 📱 Physical SIM: Simply move the card to the new phone. If the slot size does not match (for example, from nano-SIM to micro-SIM), use an adapter.
• 📲 eSIM:
  1. On the old phone, delete the eSIM profile (if it is linked to the device).
  2. Get a new QR code from your operator.
  3. Activate the eSIM on the new phone.

⚠️ On some phones (for example, iPhone) the eSIM is tied to the Apple ID, and the transfer may require additional steps.

Is it possible to use two lines of one operator?

Technically yes, but there are nuances:

• 📶 One operator, two numbers: You can register for a second number with the same operator (for example, MTS offers the MultiSIM service).
• 💰 Tariffs: Check whether your tariff supports multiple lines. For example, Beeline allows up to 5 SIMs on one account, but with restrictions.
• ⚠️ Limitations: Some operators block the use of two of their SIMs in one phone (for example, to prevent fraud).