An iPhone that won’t charge — or that charges painfully slowly — is one of the most stressful tech problems to run into, especially when you need your phone for the day ahead. The good news is that charging issues are rarely caused by a dead battery. More often, the culprit is a worn cable, a dirty charging port, a misbehaving accessory, or a software setting quietly limiting how fast your phone charges. This guide walks through how to diagnose the problem and the fixes that actually work, from the simplest checks to the ones worth a trip to Apple.
What You’ll Need
- Your iPhone and its charging cable
- A different Lightning or USB-C cable and wall adapter, if you have access to one
- A flashlight (even your other phone’s) to inspect the charging port
- A soft, dry, anti-static brush or a wooden toothpick (never metal) for port cleaning
- A few minutes to test different charging combinations
Start With the Basics
Before assuming the worst, rule out the obvious. Try a different cable and a different wall adapter if you have them — cable failure is the single most common cause of charging problems, since the connector points bend and fray with daily use. Also try a different power outlet, in case the outlet or a power strip is the issue rather than your phone.
Restart your iPhone as well. A frozen or glitching system process can occasionally interfere with how the device communicates with a charger, and a simple restart clears that out.
Inspect and Clean the Charging Port
Lint, pocket dust, and debris build up inside the charging port over time and can physically block the cable from making a full connection. With the phone powered off:
- Shine a flashlight into the port and look for visible lint, dust, or debris.
- If you see buildup, gently use a soft anti-static brush or a wooden toothpick to loosen and remove it. Never insert anything metal or sharp, and avoid compressed air, which can push debris deeper or damage internal components.
- Once the port looks clear, try charging again with a cable you know works.
Check for a Liquid-Detection Warning
If your iPhone shows a “Liquid Detected in Lightning Connector” or similar alert, it has sensed moisture in the port and disabled charging to protect the phone. If this happens, unplug the cable, gently tap the phone (connector facing down) to help any liquid drain out, and leave it in a dry, room-temperature area for at least a few hours before trying to charge again. Do not use rice, heat sources, or compressed air, as none of these are reliable or safe methods.
Check Your Charging Cable and Adapter Are Genuine or MFi-Certified
Uncertified or damaged third-party cables can cause slow charging, intermittent charging, or in some cases no charging at all, since the iPhone may limit power delivery from an accessory it can’t verify. Look for the “Made for iPhone” (MFi) label on cable packaging, and consider testing with an Apple-supplied or MFi-certified cable to see if charging improves.
Why Charging Might Be Slow (Even When It’s Working)
If your iPhone is charging but very slowly, a few common factors are usually responsible:
- Low-power USB source: Charging from a computer’s USB port or a low-wattage adapter is significantly slower than a higher-wattage wall adapter.
- Using the phone while charging: Gaming, video streaming, or navigation while plugged in draws power as fast as the charger supplies it, slowing the net charge rate.
- Optimized Battery Charging: This iOS feature intentionally slows charging past 80% in certain conditions to reduce long-term battery wear. It’s a feature, not a fault.
- Extreme temperatures: iPhones can throttle charging speed automatically if the device is too hot or too cold.
- Battery health decline: An older battery with reduced maximum capacity may charge and discharge less efficiently overall.
You can check your battery’s condition under Settings > Battery > Battery Health & Charging, which shows maximum capacity relative to when the battery was new.
Update iOS
Apple occasionally ships fixes for charging-related bugs in software updates. Go to Settings > General > Software Update and install any available update, since an outdated version of iOS can occasionally cause erratic charging behavior.
Common Problems and Fixes
Phone shows the charging symbol but the percentage isn’t moving. This often means the power source is too weak to keep up with the phone’s current usage. Try a higher-wattage adapter and stop using the phone while it charges.
Phone only charges when the cable is held at a specific angle. This usually points to a damaged cable or a loose-fitting port connection, either from a worn cable end or debris in the port. Try a new cable first, since it’s the cheaper and more common fix.
Phone gets hot while charging. Some warmth is normal, especially with fast charging or while using the phone. If it becomes uncomfortably hot, remove any case, avoid using the phone while it charges, and let it cool before continuing.
Nothing works after trying cables, ports, and restarts. At this point, the issue may be with the battery, charging IC, or another internal component. It’s worth booking a Genius Bar appointment or visiting an Apple Authorized Service Provider for a diagnostic rather than continuing to troubleshoot blindly.
A Note on Data Safety
If your iPhone won’t charge at all and the battery is critically low, back up important data as soon as you get any charge on the device. Use Settings > [your name] > iCloud > iCloud Backup, or connect to a computer for a local backup, so that your photos, messages, and app data are protected if the device eventually needs a battery replacement or a full reset. This matters most if you end up handing the phone to a third-party repair shop, since a fresh backup means you won’t lose anything if something goes wrong during service.
FAQ
Q: Is it bad to leave my iPhone plugged in overnight?
A: No. iPhones use Optimized Battery Charging and internal safeguards to prevent overcharging, so leaving it plugged in overnight is safe for the battery.
Q: Why does my iPhone charge faster with one cable than another?
A: Charging speed depends on both the cable and the power adapter’s wattage. A cable or adapter that doesn’t support fast charging will charge more slowly, even if the phone itself is capable of faster charging.
Q: Can a case cause charging problems?
A: A thick case, or one with metal components or a built-in wallet, can sometimes interfere with wireless charging alignment or trap heat during wired charging. Try charging with the case off if you’re having trouble.
Q: Should I use wireless charging if my port seems damaged?
A: Yes, a wireless charger (Qi or MagSafe) is a good temporary workaround if you suspect port damage, since it bypasses the physical connector entirely while you arrange a repair.
Steps and menu labels may change as apps update. Last updated: July 2026.