SIM Card Not Working on Android or iPhone

Quick Answer

When your phone displays No SIM, Invalid SIM, SIM Failure, or cannot connect to the carrier, first restart the phone and confirm that Airplane Mode is off.

For a physical SIM, power the phone off and carefully reseat the card. Then test the SIM in another compatible phone or test a known-working SIM in your phone. This comparison is more useful than immediately resetting the device because it helps separate a damaged or inactive SIM from a phone-side problem.

Choose the Symptom That Matches

What you see	What it may suggest	First safe step
No SIM or No SIM Card Detected	The card may be inactive, incorrectly installed, damaged, or unreadable	Restart, then reseat the SIM
Invalid SIM or SIM Not Supported	Carrier lock, activation, compatibility, or SIM condition may be involved	Check the plan and carrier
SIM Failure	The card, account, tray, or phone may be involved	Test the SIM in another phone
SIM appears but has no signal	Coverage, carrier outage, registration, or account problem may be involved	Test another location
Signal appears but mobile data does not work	This is not strictly a SIM-detection problem	Use the mobile-data guide
One SIM works but another does not	The failing SIM or its carrier account becomes more relevant	Contact that carrier
No SIM works in one phone	The phone’s tray, reader, software, or cellular hardware may be involved	Seek device support
Physical SIM works but eSIM does not	The eSIM profile or carrier activation may be involved	Contact the carrier
Enter SIM PIN or PUK appears	The SIM is security-locked	Obtain the correct code from the carrier

A SIM-related message does not prove that the card itself is damaged. Activation, carrier restrictions, improper installation, device settings, and phone hardware can produce similar symptoms.

Safety Check

Power the phone off before removing a physical SIM unless the manufacturer’s instructions specifically state otherwise.

Stop and seek support when:

• The SIM tray is bent, cracked, jammed, or will not close fully.
• The phone was recently dropped or exposed to liquid.
• The SIM contacts show heavy corrosion or burning.
• The tray requires excessive force to remove or insert.
• The eject tool does not enter the correct tray-release hole.
• More than one known-working SIM fails after physical damage.

Do not:

• Scrape the SIM contacts or tray.
• Insert tools into the phone’s microphone opening.
• Apply alcohol, water, or cleaning chemicals inside the SIM slot.
• Force an incorrectly sized SIM into the tray.
• Use a hand-cut SIM that does not sit flat.
• Open the phone to access its internal SIM reader.

1-Minute Safe Checks

Complete these checks before resetting network settings:

1. Turn Airplane Mode off.
2. Restart the phone.
3. Confirm that the carrier account and mobile plan are active.
4. Check whether the phone displays the carrier name.
5. Move to another location with known carrier coverage.
6. Confirm that the correct SIM is enabled on a dual-SIM phone.
7. Check for a phone software update.
8. Note the exact message: No SIM, Invalid SIM, SIM Failure, or No Service.
9. Test calls, text messages, and mobile data separately.
10. Check whether another phone using the same carrier has service nearby.

Fix 1: Restart the Phone and Reconnect to the Carrier

SAFE FIRST CHECK

Use This When

Use this when the SIM stopped working suddenly without a drop, liquid exposure, SIM replacement, or account change.

Why It May Help

Restarting forces the phone to reload its cellular services and attempt a new connection with the carrier. Samsung and Apple both include restarting among their official first steps for No SIM or Invalid SIM errors.

Steps

1. Turn Airplane Mode on.
2. Wait approximately 10 seconds.
3. Turn Airplane Mode off.
4. Restart the phone.
5. Wait for the carrier name and signal indicator to return.
6. Try a call, text message, and mobile-data connection.

Expected Result

The SIM should reconnect if the problem was caused by a temporary cellular-service or registration failure.

What the Result Means

• If service returns, a temporary phone or carrier connection problem was involved.
• If the phone still displays No SIM, continue with the SIM activation and installation checks.

Fix 2: Confirm That the SIM and Carrier Account Are Active

DIAGNOSTIC TEST

Use This When

Use this when:

• The SIM is new.
• The SIM was transferred from another phone.
• Your plan recently expired or changed.
• The phone displays Invalid SIM.
• Calls, texts, and mobile data all stopped.
• The eSIM was recently installed or transferred.

Steps

1. Sign in to your carrier account through its official app or website.
2. Confirm that the mobile line is active.
3. Check for an unpaid balance, expired prepaid registration, suspended plan, or incomplete activation.
4. Confirm that the SIM or eSIM is assigned to your phone number.
5. Contact the carrier when the account information is unclear.
6. Ask the carrier to verify:
   • SIM activation
   • Account provisioning
   • eSIM profile status
   • Device compatibility
   • Carrier lock or network restrictions
   • Local outages

Apple specifically recommends confirming an active wireless plan before proceeding with its other Invalid SIM and No SIM steps. Google also directs users to the carrier when a SIM or carrier service has a problem.

Expected Result

The carrier should confirm whether the SIM is active and allowed to connect.

What the Result Means

• If the carrier activates or reprovisions the line and service returns, the issue was account-side rather than physical SIM damage.
• If the carrier confirms that the SIM is active, continue with the phone-side checks.

Fix 3: Make Sure the SIM Is Enabled on Android

CONDITIONAL STEP

Use This When

Use this on Android when the SIM appears in Settings but is disabled, gray, or not selected for service.

Google Pixel Steps

1. Open Settings.
2. Tap Network & internet.
3. Tap SIMs.
4. Select the carrier.
5. Turn on Use SIM.
6. If the phone has more than one SIM, confirm that the intended SIM is selected for:
   • Calls
   • Text messages
   • Mobile data
7. Turn Airplane Mode on and off.
8. Test the connection.

Google documents that an existing Pixel SIM may be inactive until Use SIM is enabled. Its exact menu path applies to Pixel phones; other Android manufacturers may use different labels.

Other Android Phones

Search Settings for:

• SIM manager
• SIM cards
• Mobile network
• Cellular network
• Dual SIM
• Use SIM

Do not assume that the Pixel path applies exactly to Samsung, Xiaomi, OPPO, realme, vivo, Motorola, or other Android devices.

Expected Result

The selected SIM should become active and attempt to register with the carrier.

What the Result Means

• If enabling the SIM restores service, the card was disabled in the phone’s settings.
• If the SIM does not appear in Settings at all, continue with the physical inspection or eSIM section.

Fix 4: Check Carrier Lock and Carrier Settings on iPhone

OFFICIALLY DOCUMENTED STEP

Use This When

Use this when an iPhone displays Invalid SIM, particularly after inserting a SIM from another carrier.

Check Carrier Lock

1. Open Settings.
2. Tap General.
3. Tap About.
4. Find Carrier Lock.
5. If the iPhone is unlocked, it should display No SIM restrictions.
6. If a restriction appears, contact the carrier that locked the iPhone.

Check for a Carrier Settings Update

1. Connect the iPhone to Wi-Fi.
2. Open Settings.
3. Tap General.
4. Tap About.
5. Wait several seconds.
6. Tap Update if a carrier-settings prompt appears.
7. Restart the iPhone.
8. Check whether the SIM is recognized.

Apple includes both carrier-lock verification and carrier-settings updates in its current Invalid SIM and No SIM guidance.

Expected Result

A compatible active SIM should be accepted after any required carrier update or unlocking process.

What the Result Means

• If the iPhone is carrier-locked, phone resets will not remove that restriction.
• If it is unlocked and the plan is active, continue with the physical SIM test.

Fix 5: Reseat and Inspect the Physical SIM

OFFICIALLY DOCUMENTED STEP

Use This When

Use this when the phone shows No SIM, the problem began after changing phones, or the physical SIM may not be seated correctly.

Steps

1. Power the phone off.
2. Remove its case if the case blocks the SIM tray.
3. Locate the correct SIM-tray eject hole using the manufacturer’s manual.
4. Use the supplied SIM tool or an appropriate eject tool.
5. Press gently until the tray releases.
6. Remove the tray without twisting it.
7. Inspect the SIM for:
   • Cracks
   • Deep scratches
   • Bending
   • Corrosion
   • Stains
   • Incorrect size
8. If there is light dust, wipe only the removable SIM card with a clean, dry microfiber cloth.
9. Align the SIM correctly with the tray’s shaped corner.
10. Make sure the SIM sits flat.
11. Reinsert the tray in its original orientation.
12. Confirm that it closes fully and is not loose.
13. Turn the phone on.
14. Wait for carrier service to appear.

Google, Apple, and Samsung all document correct SIM placement or reseating. Google and Samsung also advise inspecting the card and using a dry cloth when appropriate.

Expected Result

The phone should detect the SIM if improper placement or a temporary contact problem was responsible.

What the Result Means

• If reseating works, the SIM was probably not making a reliable connection.
• If the tray does not close correctly, do not force it. Confirm that the SIM and tray match the exact phone model.

Fix 6: Cross-Test the SIM and the Phone

DIAGNOSTIC TEST

Use This When

Use this after restarting and reseating the physical SIM.

Test A: Put the SIM in Another Compatible Phone

1. Power both phones off.
2. Insert the affected SIM into another carrier-compatible phone.
3. Turn the second phone on.
4. Wait for the carrier connection.
5. Test a call, text message, and mobile data.

Test B: Put a Known-Working SIM in the Affected Phone

1. Obtain a compatible active SIM with the owner’s permission.
2. Power the affected phone off.
3. Insert the known-working SIM.
4. Turn the phone on.
5. Test carrier service.

Apple, Google Pixel, and Samsung recommend testing another SIM or another phone to isolate the affected component.

What the Results Mean

Test result	What it may suggest	What it does not prove
Your SIM fails in two compatible phones	The SIM or carrier account becomes more likely	It does not prove physical damage
Your SIM works in another phone	The original phone becomes more relevant	It does not identify the failed phone component
Another SIM works in your phone	Your original SIM or account becomes more relevant	It does not prove the tray is perfect
No working SIM is detected by your phone	Tray, reader, software, or cellular hardware may be involved	It does not prove motherboard failure
Both SIMs work after reinsertion	A temporary contact or registration issue may have occurred	It does not guarantee the problem cannot return

This comparison provides stronger diagnostic information than repeatedly restarting or resetting the phone.

Fix 7: Troubleshoot an eSIM Separately

CONDITIONAL STEP

Use This When

Use this when the phone uses an eSIM or downloaded carrier profile instead of a removable card.

Steps

1. Connect the phone to reliable Wi-Fi.
2. Restart the phone.
3. Confirm that the eSIM line appears in the phone’s SIM or cellular settings.
4. Confirm that the line is turned on.
5. Check whether the correct line is selected for calls and mobile data.
6. Contact the carrier and ask it to verify:
   • eSIM activation
   • Profile assignment
   • Transfer status
   • Device eligibility
   • Account provisioning
7. Follow only the carrier’s official activation or transfer instructions.

Do not delete an eSIM profile as a routine first step. Restoring it may require a new activation code, carrier app, identity verification, or carrier assistance.

Apple directs users with an eSIM-related No SIM or Invalid SIM problem to their carrier. Google also notes that SIM activation and eSIM availability depend on the carrier.

Expected Result

The carrier should restore or replace the eSIM profile when activation or provisioning is responsible.

What the Result Means

• A physical SIM replacement cannot fix an eSIM-profile problem.
• If several properly activated eSIM profiles fail on the same phone, manufacturer support may be required.

Fix 8: Install Phone Software Updates

SAFE FIRST CHECK

Use This When

Use this when the SIM problem began after a software update, phone setup, carrier change, or eSIM transfer.

Android

1. Connect to Wi-Fi.
2. Open Settings.
3. Search for System update or Software update.
4. Install an appropriate available update.
5. Restart the phone.
6. Test the SIM.

iPhone

1. Connect to Wi-Fi.
2. Open Settings.
3. Tap General.
4. Tap Software Update.
5. Install an appropriate update.
6. Return to Settings → General → About.
7. Accept a carrier-settings update if prompted.
8. Restart the iPhone.

Expected Result

The phone should run its current cellular software and carrier configuration.

What the Result Means

An update may correct a software or compatibility problem, but it cannot activate a suspended SIM, repair a bent tray, or make an incompatible carrier-locked phone accept another network.

Fix 9: Reset Mobile Network Settings on Supported Android Phones

CONDITIONAL STEP

Use This When

Use this only when:

• The SIM is physically detected.
• The carrier confirms that the line is active.
• The phone has no visible physical damage.
• Restarting and updates did not help.
• The problem began after changing network settings.

Google Pixel Steps

1. Open Settings.
2. Tap System.
3. Tap Reset options.
4. Tap Reset mobile network settings.
5. Read the displayed warning.
6. Confirm the reset.
7. Restart the phone.
8. Test the SIM.

Samsung Galaxy Steps

1. Open Settings.
2. Tap General management.
3. Tap Reset.
4. Tap Reset mobile network settings.
5. Read the displayed warning.
6. Confirm the reset.
7. Restart and test the phone.

Google documents a Pixel mobile-network reset, while Samsung documents its own Galaxy-specific reset path. These menu paths should not be presented as universal Android instructions.

Important Limitation

A network reset cannot repair:

• A damaged SIM
• A bent tray
• A broken SIM reader
• A carrier suspension
• An incompatible carrier lock
• An inactive eSIM profile
• An outage

Expected Result

The phone should attempt to reconnect using its default mobile-network configuration.

What the Result Means

If the SIM remains completely undetected, repeating the network reset is unlikely to provide additional value.

Fix 10: Ask the Carrier to Test or Replace the SIM

PROFESSIONAL INSPECTION RECOMMENDED

Use This When

Contact the carrier when:

• The SIM fails in more than one compatible phone.
• The SIM is bent, cracked, corroded, or badly scratched.
• The plan is active but the SIM remains unregistered.
• A PUK code is required.
• An eSIM cannot be activated.
• The SIM was transferred from an older or incompatible device.
• The carrier needs to reprovision the line.
• The phone reports SIM Not Supported or Invalid SIM.
• A replacement SIM is required.

Ask the carrier to:

1. Verify the account and plan.
2. Check the SIM’s activation status.
3. Confirm that the phone is compatible.
4. Check whether the device is carrier-locked.
5. Test the SIM in a carrier device.
6. Replace the physical SIM when appropriate.
7. Issue or transfer an eSIM when supported.
8. Confirm local outages or registration problems.

Google advises contacting the carrier when the phone displays a SIM or carrier-service error. Apple and Samsung also recommend carrier testing or SIM replacement when the card remains undetected.

When the Problem May Be Phone Hardware

A phone-side hardware problem becomes more plausible when:

• Multiple active, compatible SIM cards fail in the same phone.
• The affected SIM works in another phone.
• The SIM tray is loose, bent, cracked, or will not close.
• The problem began after a drop or liquid exposure.
• Cellular service disappeared along with other phone hardware problems.
• The phone repeatedly changes between No SIM and detected without moving.
• An authorized carrier confirms that the SIM and account are working.
• Manufacturer-specific diagnostics identify a cellular hardware issue.

These results do not identify the exact damaged component. The issue could involve the tray, contacts, SIM reader, antenna system, modem, logic board, or another internal connection.

Do not open the phone or attempt component-level repairs without the correct service documentation and equipment.

When to Stop DIY Troubleshooting

Stop and seek carrier or manufacturer support when:

• The SIM tray is physically damaged.
• Liquid entered the SIM slot.
• The phone becomes unusually hot near the SIM area.
• No known-working SIM is detected.
• The carrier confirms that the account and SIM are active.
• A replacement SIM produces the same result.
• The phone cannot complete cellular activation.
• The problem began after a hard drop.
• The next proposed step would require opening the phone.

A factory reset is not a normal fix for a SIM-detection problem. It can erase personal data while failing to resolve a damaged SIM, inactive carrier account, bent tray, carrier lock, eSIM activation problem, or defective SIM reader.

When This Guide Is Not the Correct Troubleshooting Path

Use a different guide when:

• The SIM is detected but the signal is weak.
• LTE or 4G is missing while other network types still work.
• The phone shows LTE or 5G but has no internet.
• Mobile data repeatedly disconnects.
• Only internet speed is slow.
• Calls fail while mobile data works normally.

These symptoms may involve coverage, network modes, APN settings, carrier congestion, or other connectivity conditions rather than SIM detection.

Common Mistakes

• Assuming that every No Service message means the SIM is damaged.
• Resetting the phone before testing the SIM in another device.
• Using a SIM tray from another phone model.
• Forcing a SIM into the wrong orientation.
• Cutting a larger SIM by hand.
• Scraping the SIM contacts.
• Applying liquid inside the SIM slot.
• Deleting an eSIM before obtaining carrier instructions.
• Entering random SIM PIN or PUK codes.
• Assuming a network reset repairs physical damage.
• Replacing the phone before asking the carrier to test the SIM.
• Factory-resetting for a problem limited to SIM detection.

Frequently Asked Questions

Related Guides

• Weak Signal Problem Fix on Android– use this when the SIM is detected but reception remains weak.
• LTE Not Working on Android – use this when the SIM works but LTE or 4G does not appear.
• Mobile Data Connected but No Internet Fix – use this when a cellular indicator appears but websites and apps cannot access the internet.
• SIM Card Detected but No Signal
• SIM Card Not Detected

Official Sources

Official sources checked: July 26, 2026

Google Android Help

Page: Complete your Android setup

Direct verified URL: https://support.google.com/android/answer/12759275?hl=en

URL status: Verified accessible during the July 26, 2026 research session. A final recheck received a temporary rate-limit response.

Supports:

• Correctly placing a SIM in the phone’s SIM tray
• Recognizing that tray designs vary by device
• Contacting the carrier when SIM or carrier services produce errors

Scope limitation:
This page provides general Android setup guidance rather than detailed troubleshooting for every manufacturer.

Google Pixel Phone Help

Page: Fix mobile connectivity issues

Direct verified URL: https://support.google.com/pixelphone/answer/14116080?hl=en

URL status: Verified accessible on July 26, 2026

Supports:

• Enabling Use SIM
• Checking SIM activation and installation
• Inspecting for bending or damage
• Cleaning a removable SIM with a microfiber cloth
• Testing another SIM or another phone
• Resetting Pixel mobile-network settings
• Contacting the carrier about outages and plan changes

Scope limitation:
Exact menu paths apply to supported Google Pixel phones. Other Android manufacturers use different interfaces.

Apple Support Philippines

Page: If you see ‘invalid SIM’ or ‘no SIM’ on your iPhone or iPad

Direct verified URL: https://support.apple.com/en-ph/108914

URL status: Verified accessible on July 26, 2026

Supports:

• Confirming an active carrier plan
• Checking iPhone Carrier Lock status
• Restarting the device
• Installing a carrier-settings update
• Contacting the carrier for eSIM problems
• Reseating a physical SIM
• Testing another SIM
• Seeking service when the alert remains

Scope limitation:
This guidance applies to compatible iPhone and cellular-capable iPad models.

Samsung Support Philippines

Page: How to fix the “No SIM Card Detected” error on Samsung Galaxy devices

Direct verified URL: https://www.samsung.com/ph/support/mobile-devices/how-to-fix-no-sim-card-detected-error-on-galaxy-phone/

URL status: Verified accessible on July 26, 2026

Supports:

• Restarting a Galaxy phone
• Inspecting and correctly aligning the physical SIM
• Cleaning the SIM and tray with a clean, dry cloth
• Resetting Galaxy mobile-network settings
• Testing the SIM in another phone
• Replacing the SIM or requesting service when necessary

Scope limitation:
The steps and menu paths apply to Samsung Galaxy devices and can vary by model and One UI version.

How This Guide Was Verified

Last technically checked:
July 26, 2026

Research method:
The current Network Fix archive and related published pages were reviewed for overlap. Official Google Android, Google Pixel, Apple Philippines, and Samsung Philippines support pages were opened, their visible titles were checked, and their procedures were matched to the relevant troubleshooting sections.

Physically tested:
No documentation reviewed.

Applies to:
Supported Android phones, iPhones, physical SIM cards, and carrier-provided eSIM profiles.

Important limitation:
SIM menus, carrier-lock behavior, eSIM activation, network-reset options, SIM sizes, dual-SIM controls, and carrier requirements vary by device model, manufacturer, country, and mobile provider.

Data-loss risk:
Conditional. Restarting, checking activation, reseating a physical SIM, and testing another SIM are non-destructive. Network resets can remove connection settings. Deleting an eSIM or factory-resetting the phone is not included as routine troubleshooting.

Final Steps

• Restart the phone, confirm that the carrier account is active, and check whether the SIM is enabled. For a physical SIM, power the phone off and reseat the card carefully.
• The most useful diagnostic step is the two-way test: try the SIM in another compatible phone and try a known-working SIM in the affected phone.
• Contact the carrier when the problem follows the SIM. Contact the phone manufacturer or an authorized repair provider when multiple active SIMs fail only in the affected phone.