What To Do When Your iPhone Says No SIM

iPhone with a No SIM Card Installed message.

Original image: Pixabay

When your iPhone can't connect to cellular phone networks, you can't make and receive calls or use 4G LTE wireless data. There could be a number of reasons for why you can't connect to a cellular network, including that the iPhone doesn't recognize its SIM card, which is used to connect to these networks.

If this is happening, a No SIM Card Installed error on your iPhone will alert you. You'll also notice that the carrier name and signal bars/dots at the top of the screen are missing, or have been replaced by No SIM or Searching.

In many cases, this problem is caused by your SIM card becoming slightly dislodged. All you need to fix this is a paper clip. Even if that's not the problem, most fixes are pretty easy. Here's what to do if your iPhone says "No SIM."

Locating the SIM Card

To fix SIM card issues, you have to know where to find the card (and if you want to learn a lot more about what the SIM card is and what it does, check out What is an iPhone SIM Card?). The location depends on your iPhone model.

  • iPhone, iPhone 3G, iPhone 3GS: Look between the sleep/wake button and the headphone jack at the top of the phone for a slot with a tiny hole in it. This is the tray that holds the SIM card.
  • iPhone 4 and newer: On the iPhone 4 and newer, the SIM tray is on the right side of the phone, near the sleep/wake (or Side) button. The iPhone 4 and 4S use a microSIM. Later models have the slightly smaller, more-modern nanoSIM. 

Re-Seating the SIM Card

Since this problem is used caused by the SIM getting dislodged, the first fix you should attempt is to put it back in place. To re-seat the SIM card in its slot, get a paper clip (or use Apple's "SIM card removal tool," included with some iPhones), unfold it, and push one end into the hole in the SIM card tray. This will pop the tray out of its slot. Push it back in and make sure it's firmly seated.

After a few seconds (wait up to a minute), the No SIM Card Installed error should disappear and your regular bars and carrier name should re-appear at the top of the iPhone's screen.

If it doesn't, fully remove the SIM. Make sure the card and the slot aren't dirty. If they are, clean them. Blowing into the slot is probably OK, but a shot of compressed air is always best. Then, reinsert the SIM.

Step 1: Update iOS

If reseating the SIM card didn't work, check to see if there's an update to the iOS, the operating system that runs on the iPhone. You'll want to connect to a Wi-Fi network and have a decent amount of battery life before you do this. Install any available updates and see if that solves the problem. To update iOS:

  1. Tap Settings.

  2. Tap General.

  3. Tap Software Update.

    Three iOS screens showing General Settings icon, Software Update button, then Download and Install button
  4. If a new version is available, follow the onscreen instructions to install it.

Step 2: Turn Airplane Mode On and Off

If you're still seeing the SIM error, your next step is to turn Airplane Mode on and then off again. Doing this can reset the iPhone's connection to cellular networks and may resolve the problem. To do this:

  1. Swipe up from the bottom of the screen (or down from the top right on iPhone X) to reveal Control Center.

  2. Tap the airplane icon so that it's highlighted. This enables Airplane Mode.

  3. Wait a couple of seconds and then tap it again, so that the icon is not highlighted.

    iOS Control Center with Airplane mode button highlighted both off and on
  4. Swipe Control Center down (or up) to hide it.

  5. Wait a few seconds to see if the error is fixed.

Step 3: Restart iPhone

If your iPhone still doesn't recognize the SIM, try the all-purpose fix for many iPhone problems: a restart. You'd be surprised how many issues are solved by restarting. To restart the iPhone:

  1. Press the sleep/wake button (on the top right of early models, on the right side of more recent models).

  2. Keep pressing until a slider appears on the screen that turns off the iPhone.

  3. Let go of the button and swipe the slider left to right.

  4. Wait for the iPhone to turn off (it's off when the screen goes fully dark).

  5. Press the hold/Side button again until the Apple logo appears.

  6. Let go of the button and wait for the iPhone to restart.

If you're using an iPhone 7, 8, or X, the steps are different. In that case, check out this article for full instructions on restarting those models.

Step 4: Check for Carrier Settings Update

Another culprit behind the SIM not being recognized could be that your phone company has changed the settings for how your phone connects to its network and you need to install them. To learn more about carrier settings, read How to Update Your iPhone Carrier Settings. This process is easy:

  1. Tap Settings.

  2. Tap General.

  3. Tap About.

  4. If an update is available, a window will pop up. Tap it and follow the onscreen instructions.

Step 5: Test for a Malfunctioning SIM Card

If your iPhone still says it has no SIM, your SIM card could have a hardware problem. One way to test this is by inserting a SIM card from another cell phone. Make sure to use the correct size – standard, microSIM, or nanoSIM – for your phone. If the No SIM Card Installed warning disappears after inserting another SIM, then your iPhone SIM is broken. You can get a new one from Apple or your phone company.

Step 6: Make Sure Your Account Is Valid

It's also possible that your phone company account isn't valid. In order for your phone to be able to connect to a phone company network, you need a valid, active account with a phone company. If your account has been suspended, canceled, or has some other problem, you may see the SIM error. If nothing has worked so far, check with your phone company that your account is OK.

Step 7: If Nothing Works

If all of these steps don't solve the problem, you have a problem that you can't fix. It's time to call tech support or to take a trip to your closest Apple Store. Get step-by-step instructions on how to do this in How to Make an Apple Store Appointment.