Seeing that "No SIM card detected" or "Insert SIM card" message on your Galaxy Z Fold 6 can stop you in your tracks. You can't make calls, send texts, or use mobile data. The good news is this is usually a simple fix, often related to the SIM tray or a software hiccup, and you can probably solve it yourself in a few minutes.
I'd start with the simplest solution first. Grab the SIM ejector tool that came with your phone. Power the phone down completely, then gently push the tool into the tiny hole on the frame to pop out the SIM tray. Take the SIM card out, give the gold contacts a quick wipe with a dry microfiber cloth, and carefully reinsert it, making sure it's seated correctly in the tray. A bit of dust or a slightly misaligned card is a very common culprit.
Perform a Force Restart
If reseating the SIM didn't work, a force restart is your next best move. This clears out any temporary software glitches that might be preventing the phone from reading the card. On the Z Fold 6, press and hold the Volume Down button and the Side (power) button together for about 10 seconds.
Keep holding until you see the Samsung logo appear on the screen, then let go. This is different from a normal restart and often fixes odd detection issues.
Check Your SIM Card Manager Settings
It's worth making sure the phone's software hasn't accidentally turned the SIM off. Unfold your phone and open the Settings app. Tap on Connections, then select SIM card manager.
Here, you'll see your SIM listed. Make sure the toggle switch next to it is turned on. If you're using dual SIMs, check that the correct one is set as your preferred line for calls and data.
Toggle Airplane Mode
This old trick still works wonders. Swipe down twice from the top of your screen to open the full Quick Settings panel. Tap the Airplane mode icon to turn it on, wait about 10 seconds, then tap it again to turn it off.
This forces your phone's modem to completely reset its connection to the network, which can sometimes kick a stubborn SIM card back into recognition.
Inspect and Clean the SIM Card and Tray
Let's take a closer physical look. Power off your Z Fold 6 and remove the SIM tray again. This time, inspect the SIM card's gold contacts for any scratches, discoloration, or corrosion. Even a small amount of pocket lint can cause problems.
Clean the contacts gently with a soft, dry cloth. While the tray is out, use a can of compressed air to give the SIM slot inside the phone a quick blast. This can dislodge any dust that's accumulated, which is a known consideration for foldable phones with moving parts like the hinge area.
To rule out a faulty SIM card, try placing it in another compatible phone. If it's not detected there either, the card itself is likely damaged and you'll need to contact your carrier for a replacement.
Update Your Phone's Software
Outdated software can sometimes cause conflicts with network components. Samsung regularly releases updates that include bug fixes. To check, go to Settings > Software update > Download and install.
If an update is available, connect to Wi-Fi and let it install. Your phone will restart afterward. This has resolved SIM detection issues for many users after a major OS update.
Reset Your Network Settings
This step clears all your saved network configurations, like Wi-Fi passwords and Bluetooth pairings, and resets your cellular settings to default. It doesn't delete your personal files or apps. Go to Settings > General management > Reset > Reset network settings.
Tap to confirm. Your phone will reboot. Afterward, you'll need to reconnect to Wi-Fi networks and re-pair Bluetooth devices, but it often clears up persistent cellular and SIM problems.
Check and Reset APN Settings
The Access Point Name (APN) tells your phone how to connect to your carrier's mobile data network. If these settings are wrong, it can seem like the SIM isn't working. Go to Settings > Connections > Mobile networks > Access Point Names.
Tap the three-dot menu in the top right and select Reset to default. This will load the standard APN for your carrier. If you need specific settings, your carrier can provide them for you to enter manually.
Try Manual Network Selection
Sometimes letting your phone automatically choose a network fails. You can manually select your carrier instead. Head back to Settings > Connections > Mobile networks > Network operators.
Tap Search now and wait for the list to populate. Select your carrier's name from the list. This bypasses the auto-connect process and can establish a more stable link.
Consider Switching to an eSIM
The Galaxy Z Fold 6 supports eSIM technology. If your physical SIM card or the tray reader is consistently problematic, switching to a digital eSIM can be a permanent solution. Contact your mobile carrier and ask if they support eSIM activation.
They can guide you through transferring your number to an eSIM profile, which is downloaded directly to your phone, eliminating the physical card and tray entirely. This is a great modern fix for recurring hardware-related SIM issues.
