How to set up SIM- card in Xiaomi phone: a complete guide from installation to error elimination

Modern Xiaomi smartphones support one or two SIM- cards, but even experienced users sometimes have difficulty configuring them. From the wrong slot selection to problems with registering on the network, errors at this stage can deprive you of communication, mobile Internet or even damage the card. In this article, we will discuss all the stages of working with the SIM- card in Xiaomi devices: from physical installation to fine network settings, including solving typical problems.

Xiaomi phones feature hybrid slots in some models (for example, Redmi Note 12 Pro+ or POCO X5 Pro), where the second slot is combined with a microSD card connector. This means that when using two SIM- cards you lose the ability to expand memory. We will explain how to optimally distribute slots so as not to lose functionality, and also explain why sometimes the network does not catch even with the correct installation of the card.

If you’ve just bought a new Xiaomi or have trouble updating your firmware, this guide will help you avoid common mistakes. For example, many users don’t know that some regions require manual APN setup to run mobile internet, and 5G models (such as Xiaomi 13T) may require additional activation of the next generation network.

1 Preparation SIM- Card: what format is needed for Xiaomi

Before installing the card in a Xiaomi smartphone, make sure that its format matches the device slot. Most modern models (starting with the Redmi 10 and POCO M4 Pro) support nano-SIM (4FF) - the most compact standard. However, older devices (for example, Redmi 5A or Mi A1) could use micro-SIM (3FF) or even mini-SIM (2FF).

If you have a universal card (with logging for all formats), gently squeeze the nano-SIM is the most reliable option. Using adapters or trimming the card with scissors can damage the contacts or loose fit in the slot, which will cause problems with registration on the network.

• 📱 Nano-SIM (4FF): All Xiaomi models from 2018 (e.g. Redmi Note 7, Mi 9, POCO F3).
• 📱 Micro-SIM (3FF): Older models before 2017 (Redmi 4X, Mi 5).
• ⚠️ Mini-SIM (2FF): Not supported by any Xiaomi model – trimming or replacement will be required.

Note that in some regions (e.g. China), Xiaomi smartphones can be sold without support for two SIM- cards even if there are two slots. This is due to local communication standards. You can check compatibility on the official Xiaomi website in the specifications section of your model.

2 Where to insert SIM- card: slot location and correct installation

In most Xiaomi smartphones, the slot for the SIM- cards is on the left end of the device (if you look at the screen), except for models with a metal body (for example, Mi 11 Ultra), where the slot can be located on top. To remove the tray, you will need a paper clip or a special key that comes with the phone.

Installation algorithm:

1. Turn off your phone (required!) to avoid damaging your contacts.
2. Insert the paperclip into the hole next to the slot and press before clicking.
3. Gently pull out the tray and put the SIM- card(s) down the contacts.
4. Make sure the card fits tightly to the stop – it should not hang around.
5. Then put the slack back in (do not put too much effort into it!).

In hybrid slot models (e.g. Redmi Note 11 Pro), the second slot can be used either for the second SIM- card or for microSD. The SIM- card is given priority: if you insert both cards, the memory slot will be locked. To avoid confusion, the tray usually has pictograms indicating the format.

Phone off | Used the correct format (nano-SIM) | Contacts card clean and undamaged |Tray inserted before clicking-->

⚠️ Warning: If the phone doesn't see the network after installing the SIM- card, check if you've confused the sides of the card. Contacts should be downwards and the angle cut off should match the shape of the tray. In 80% of cases, the "invisibility" of the card is due to the wrong installation.

3 Activation of SIM- Card and First Network Configuration

After installing the SIM- card, turn on your phone. In most cases, Xiaomi will automatically identify the operator and connect to the network. However, manual activation is sometimes required, especially if the card is new or the phone is purchased in another region.

What to do if the network does not appear:

• 🔄 Reboot the phone — it resets the communication module.
• 📡 Turn on flight mode for 30 seconds, then turn it off.
• 🔧 Go to Settings → SIM-maps and mobile networks → [your SIM] and select the operator manually.
• 📞 Call a short carrier number (e.g. *111# for MTS) – sometimes this speeds up activation.

If you use two of them SIM-maps, in settings you can set priorities:

• 📞 Calls: Select SIM by default for outbounds.
• 🌐 Mobile data: indicate which SIM is used for the Internet.
• 📶 4G/5G: enable support for modern networks (if the operator supports).

Models with 5G support (e.g. Xiaomi 13 or POCO F5) may require additional customization. Go to Settings → SIM- cards and mobile networks → [your SIM] → Network type and select 5G (auto) or LTE/5G.

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If the phone doesn’t see the second SIM- card, try changing the slot. In some Xiaomi models, the first slot (SIM 1) has a better antenna and works more stable with the 4G/5G.

4. Mobile Internet (APN) setup in Xiaomi

If the SIM- card is not installed, the APN (Access Point Name) settings are likely not configured. This is especially true for new SIM- cards or phones purchased abroad. Most operators (MTS, Beeline, MegaFon, Tele2) automatically send settings, but sometimes they have to enter manually.

How to set up an APN on Xiaomi:

1. Go to Settings. → SIM-maps and mobile networks → [yours SIM] → Access points (APN).
2. Click on the "+" icon or select "New Access Point".
3. Fill in the fields according to your operator’s data (see the table below).
4. Save the settings and restart the phone.

If the internet is still not working after setting up, check:

• 🔄 Whether mobile data is enabled in the notification curtain.
• 📶 Whether the correct network type is selected (e.g. 4G instead of 3G).
• 💰 Is there enough money in the account (some operators block the Internet with zero balance).

5. Solving typical problems with the SIM- card in Xiaomi

Even after you install and configure the SIM- cards correctly, you can still experience failures, and let’s look at the most common problems and how to fix them.

5.1 Phone does not see SIM- card

If the status bar shows “No SIM- card” or “No service”, follow the following steps:

• 🔄 Reboot the phone.
• 📱 Check if the card is installed correctly (remove and repaint).
• 🧹 Clean the contacts of the SIM- card and slot with soft dry cloth (do not use alcohol!).
• 🔧 Update the firmware: go to Settings → The phone. → Updating the system.
• 🛠️ If nothing helps, try the SIM- card on another phone - it may be damaged.

⚠️ Warning: If the phone stops seeing the SIM- card after falling or getting moisture, don't try to disassemble it yourself, and if you need a diagnostic at a service center, you may have a slot or antenna module damaged.

5.2. no network or frequent communication

If the network indicator flashes or periodically disappears:

• 📡 Turn on and off flight mode.
• 🔄 Switch the network type from 4G to 3G or 2G (sometimes helps with unstable coverage).
• 📍 Check if you are in a low signal area (e.g., in a basement or elevator).
• 🔧 Reset network settings: Settings → System → Reset settings → Reset network settings.

In models with 5G (e.g., Xiaomi 12T Pro) it can help to disable support for 5G in the SIM- card settings – sometimes this improves the stability of the 4G.

5.3 The mobile Internet is not working.

If the Internet is not connected, the network indicator is:

• 🌐 Check the settings APN (see Section 4).
• 🔄 Reboot the phone.
• 📞 Call the operator and check if the data service is activated.
• 🔧 Enable data roaming (even if you are not roaming): Settings → SIM-maps and mobile networks → [your SIM] → data roaming.

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If the mobile internet only works after a reboot, the most likely problem is the firmware: Update MIUI to the latest version or reset the network settings.

6. Features of setting SIM- cards in different models Xiaomi

Despite the general principles, some Xiaomi models have unique nuances when working with SIM- cards.

The Redmi Note Series

Redmi Note 10/11/12 models support two SIM- cards, but in many regions the second slot is hybrid (SIM + microSD).

• 📶 In the Redmi Note 11 Pro+ 5G, the first SIM- card supports 5G, the second only supports 4G.
• 🔋 In some firmware there is a bug: when active 5G The battery goes down faster. The solution is to turn it off. 5G, if you don't need it.

6.2 POCO series

POCO phones (such as the POCO X5 Pro or POCO F4) often have “clean” firmware without the unnecessary services of Xiaomi, but because of this, automatic APN settings may not be available.

6.3 Flagship Models (Xiaomi 12/13)

In flagships (for example, Xiaomi 13 Ultra) support for eSIM, but only in some regions (for example, in Europe), this feature is usually blocked. In these models, there may be no hybrid slot - both SIM- cards are installed without losing the ability to use microSD.

Another feature of the flagships is support for Dual 5G (simultaneous operation of two SIM- cards in the 5G network). However, this feature only works with certain operators and requires manual configuration in Settings → SIM- cards and mobile networks → Dual 5G.

7 How to transfer contacts and settings from old SIM- card

If you have changed the SIM- card, but want to save contacts, use the built-in tools of Xiaomi.

• 📱 Export to phone: go to Contacts → Settings → Import/Export → Export to device. Contacts are saved to a.vcf file, which can then be imported back.
• ☁️ Sync with Mi Account: In the contact settings, enable sync with your Xiaomi account. Contacts will be available on any device after authorization.
• 🤖 Google Contacts: If you use Google services, your contacts are automatically synced to the cloud.

Important: If you are transferring contacts from an old SIM- card to a new one, make sure that the new card supports contact storage (not all operators provide this feature), otherwise the contacts will only have to be stored in the phone’s memory or the cloud.

⚠️ Warning: When exporting contacts to a.vcf file, check that all fields (phones, email, addresses) are saved correctly. Sometimes the Cyrillic characters in names may not appear correctly - in which case open the file on your computer and correct the encoding (for example, in Notepad++).

8 Security: How to protect your SIM- card from hacking

The SIM- card is not only access to calls, but also the key to many services (banking, social networks, two-factor authentication) to protect it:

• 🔒 Set PIN-code on SIM-card: Settings → SIM-cards and mobile networks → [your SIM] → Lock SIM-cards. Use a 4-8 digit code, but do not use birth dates or simple combinations (e.g., 1234).
• 🛡️ Turn off call forwarding if you don't use it: scammers can redirect your calls to their number.
• 📱 Do not store important contacts only on the SIM- card, they can be lost if it is damaged.
• 🔄 Regularly check active services with the operator (e.g., via USSD- commands like *111#) to disable unnecessary subscriptions.

If you suspect that your SIM- card has been compromised (e.g., lost money from your account or SMS comes with a confirmation code that you did not request), immediately:

1. Call the operator and block the card.
2. Change passwords from important services (bank, mail, social networks).
3. Check your phone for viruses using Google Play Protect or Dr.Web.

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If you travel frequently, consider using eSIM (if your Xiaomi model supports it), which will eliminate the need to physically change the SIM- cards and reduce the risk of losing them.

FAQ: Frequent questions about SIM-maps in Xiaomi