Why it is important to insert a SIM card in Xiaomi
Even experienced users sometimes face a problem: the SIM card is not detected, the phone asks to restart or does not see the network at all. 90% of the time, the reason is trivial – improper installation of SIM in the tray. Xiaomi smartphones (including the Redmi series, POCO and Mi) use the nano-SIM standard, but even here there are nuances: from the location of contacts to the design of the tray.
In this article, we will not only examine which side to insert the SIM, but also the typical errors that lead to the breakage of contacts or tray. For example, did you know that in models with a hybrid slot (for example, the Redmi Note 12 Pro+) the wrong installation can block the memory card slot? or that in some flagships (such as Xiaomi 14 Ultra) the tray has an asymmetrical slot to protect against improper insertion?
We collected up-to-date data on all popular models (2020-2026), added comparative photos and videos, and prepared a checklist to check the health of the SIM card after installation. If your phone suddenly stopped seeing the network, do not rush to bring it to the service: 80% of the time the problem is solved in 2 minutes.
Xiaomi SIM Standards: Nano-SIM and eSIM
Since 2018, all Xiaomi smartphones have been using the nano-SIM (4FF) format, the most compact standard with dimensions of 12.3 × 8.8 × 0.67 mm.
- 📱 Hybrid slots: In most models (e.g. Redmi Note 11, POCO X5 Pro) The second slot is combined with a microSD connector, which means you can use either two nano-SIMs or one. SIM + memory-card.
- 🔄 Models with eSIM: flagships Xiaomi 13T Pro, Xiaomi 14 and new POCO F5 The Pros support a virtual SIM card, but the physical slot still remains, usually for the second line.
- ⚠️ Outdated models: In rare cases (e.g. Redmi) 8A 2020 – Micro-SIM is still a common occurrence, but it is an exception.
How do you check which slot is on your phone? Look at the specs on Xiaomi's official website or look at the tray: if there's a hole under the paper clip on the side, it's a hybrid slot. If the hole is just on top, it's likely two separate SIM slots.
Which side to insert the SIM: step-by-step instructions
The basic rule is that the SIM card contacts should be downward and the bevelled angle should match the slot in the tray, but the devil is in the details.
- Turn off your phone (optional, but recommended for safety).
- Find a tray for the SIM – it is usually on the upper or side edge (in the POCO F4 GT – on the right, in the Redmi 10C – on the left).
- Insert a paper clip (or a special key from the kit) into the tray hole until it is pushed out.
- Put the SIM card on the tray so that: 🔹 Golden contacts looked down (to the base of the tray). 🔹 The sloping angle coincided with the groove (usually in the upper left corner). 🔹 The map fits tightly to the accent - there should be no backlash.
Carefully insert the tray back before the click. Don't make any effort!
If the tray doesn't come in, don't push. The SIM card is probably not installed correctly. Remove the tray and check again.
Is the phone off?|Does the sloping corner of the card match the groove of the tray?|SIM card contacts point down?|The tray is inserted effortlessly?-->
Photos and diagrams for popular Xiaomi models
The visual instructions will help to avoid errors. Below is a comparison table with the correct location of the SIM card for different series:
| Model | Slot type | The correct position of the SIM | Notes |
|---|---|---|---|
| Redmi Note 12/13 | Hybrid | The tray is on the right. It supports 5G. | |
| POCO X5 Pro | Hybrid | The second slot is for nano-SIM or microSD only. | |
| Xiaomi 13T/14 | Double nano-SIM | It supports eSIM for the first line. | |
| Redmi A2 | Hybrid | The tray is fragile - don't make any effort! |
Note that in metal-framed models (such as the Xiaomi 12S Ultra), the tray may have an additional lock, and if it doesn't click, the SIM card is curved.
What if the tray is jammed?
Common Mistakes and How to Avoid Them
Even a slight mistake in installing a SIM card can lead to serious problems, and here are the most common mistakes and their consequences:
- ❌ Inverted contacts: SIM card undetected, phone says "No service." Solution: Turn the card over and reboot the device.
- ❌ Skewered angle mismatch: The tray doesn't stand up or the curve enters. Solution: Check the groove - in some models (e.g., for example, POCO M5) He's shifted to the right.
- ❌ Using micro-SIM without adapter: Contacts do not touch the connector Solution: Cut the card to nano-SIM or use an adapter.
- ❌ Severe pressure on the tray: The mechanism may bend or the antenna contact may come off. Solution: If the tray does not enter, remove and check again.
⚠️ Note: In models with support 5G (For example, the Redmi Note 12 Pro+) misplacement SIM This may cause the phone to only work in the mode. 4G. This is because the contacts for the high-frequency bands are located closer to the edge of the map.
If the SIM card is not determined after installing it correctly, try the following steps:
- Wipe the SIM card contacts with a smoother (without pressing!).
- Restart your phone in Safe Mode (press the power button → “Reboot Safe Mode”).
- Check the network settings: Settings → SIM-maps and mobile networks → Select the network (select "Automatically").
What to do if the SIM card is not determined
If you are sure that the SIM card is installed correctly, but the phone does not see it, the problem may be as follows:
| Symptoms. | Possible cause | Decision |
|---|---|---|
| The phone doesn't see the SIM, but the tray is inserted correctly | Contact contamination | Wipe SIM contacts and tray with alcohol |
| There is a message "wrong SIM" | SIM card damaged or blocked | Try a different SIM or contact the operator |
| The phone sees SIM, but no network | Wrong APN settings | Reset network settings: Settings → Data transfer → APN reset |
| The tray is not fixed, falls out | Breakage of the retainer | Use Scotch for Temporary Fixing or Replace the Tray |
If none of the methods worked, check:
- 📶 Does the SIM card work on another phone?
- 🔧 Is there any physical damage to the tray (bent contacts, cracks)?
- 📱 Is the phone software updated? In some models (e.g. Redmi) 9A) bug SIM corrected in updates.
⚠️ Warning: If after installing the SIM card, the phone starts to overheat or discharge quickly, immediately remove it.
💡
If you change your SIM cards frequently, buy a magnetic tray (for example, for the Xiaomi 13 Pro).It allows you to retrieve the SIM without a clip and reduces the risk of damage to contacts.
Features of SIM installation in hybrid slots
Hybrid slots (such as the Redmi Note 11 Pro+ or POCO X4 Pro) require special attention.
- 🔀 Slots priority: Usually SIM1 (top slot) supports 5G, SIM2 — only 4G. If you need top speed, install the main SIM card in the first slot.
- 📱 MicroSD conflict: If you use a memory card, the second is SIM In some models (e.g. Redmi 10 2022), this can be bypassed through the engineering menu, but officially the function is not supported.
- ⚡ Energy consumption: two active SIM-If you don't need the second line all the time, turn it off in the settings.
How to check which slot is active? Go to Settings → SIM-And you can see here what SIM card is used for calling, SMS And the mobile Internet, for example, Xiaomi. 12T Different networks can be assigned to different tasks:
- SIM1 - calls and SMS,
- SIM2 is just the Internet.
💡
In hybrid slots, you can’t use two SIMs and microSDs at the same time, and the SIM card in the first slot will be faster and more stable.