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01The 60-second check
If your power bank is not charging your phone, start with the cable and the button. Most banks only switch their output on when you press the button or plug something in, and a worn cable fails on a bank long before it fails on a strong wall charger.
Still nothing? Match what you're seeing in the table below, then work through the steps.
02What the symptom tells you
| What happens | Most likely cause | First thing to try |
|---|---|---|
| Nothing at all, bank lights off | Bank is empty or in deep sleep | Recharge the bank for an hour, then retry |
| Charges for a few seconds, then stops | Bank shuts off because the draw is too low, or the phone is full | Turn on low-current mode, or press the button again |
| Lights on, phone shows nothing | Bad cable or lint in the phone's port | Swap the cable, clean the port |
| Phone charges, but painfully slowly | USB-A port, weak bank output or thin cable | Use the USB-C PD port with a USB-C cable |
| USB-C to USB-C: the bank's level goes up | Power is flowing from the phone to the bank | Unplug, press the bank's button, then reconnect |
| Magnetic bank: no charging icon | Case too thick or phone off-center | Case off, recenter, or use its cable |
USB-C ports can send power both ways. If a bank with a single USB-C port is nearly empty, some phones end up topping up the bank instead. Press the bank's button first, and plug into its dedicated output port if it has one.
03Fix it, step by step
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Wake the output
Press the power button once, then connect the phone within a few seconds. Many banks turn the output off after a short idle period to save power.
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Swap the cable
Use a cable that charges this phone from a wall plug. Short cables that live in bags with a bank take a beating at the neck. Our guide to why cables break shows what to look for.
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Try another port
Banks often have one USB-C port and one or two USB-A ports, and they don't all behave the same. The USB-C port is usually the one marked PD and the fastest for phones.
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Clean the phone's port
Lint packed in the port stops the plug seating fully, so the phone may charge from a firm wall cable but not a loose one. Use a wooden toothpick or a soft brush, never metal. See how to clean a USB-C port.
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Recharge the bank fully
Banks reserve their last few percent and stop output early to protect the battery. If it's showing one light, charge it to full and try again.
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Let everything cool
Phones and banks both pause charging when hot. Take the phone out of a thick case, keep both out of the sun, and give them 10 minutes.
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Test with another device
If the bank charges earbuds or another phone but not yours, the issue is on the phone side: the port, a setting like a charge limit, or the phone needing a restart.
04Earbuds, watches and the auto shut-off problem
Small devices draw very little current. Many power banks read that as "nothing connected" and switch off after a short time, which is why earbuds or a fitness tracker start charging and stop moments later.
Lots of banks include a low-current or trickle mode for exactly this. It's usually switched on by double-pressing or long-pressing the power button, and the bank's light changes color or pattern to show it. The exact press varies by brand, so check your bank's manual.
Charge the earbuds and your phone at the same time from two ports. The phone's higher draw keeps the bank awake, and the earbuds charge alongside it.
05Wireless and magnetic power banks
A magnetic power bank charges through the back of the phone, so it has the same weak points as a wireless charger: distance, alignment and heat. Thick cases, wallets and metal plates between the two stop it cold.
- Use a case with built-in magnets if your phone needs one. A MagSafe-compatible case holds the bank on the charging coil.
- Unplug the phone's cable. Many phones ignore wireless charging while a USB cable is connected.
- Expect warmth and slower charging. Wireless loses more energy as heat than a cable. If speed matters, plug the phone into the bank's USB-C port instead.
For iPhone-specific wireless issues, see iPhone not charging wirelessly.
06When the bank is the problem
If the bank itself won't take a charge, that's a different fault with its own fixes in power bank won't charge. If it charges but runs flat after half a phone charge, the cells have probably aged. Lithium cells lose capacity with every cycle, and a bank that's swollen, dented or hot should be retired, not fixed.
Display models show the real level, and USB-C PD ports charge phones properly.
Not sure how many charges a new bank will give your phone? Try the power bank charge calculator.
Questions people ask
Why is my power bank on but not charging my phone?
Usually a bad cable, lint in the phone's port, or a port on the bank that's slow or switched off. Try a cable that works from the wall, clean the port, and use the bank's USB-C PD port.
Why does my power bank stop charging after a few seconds?
The bank thinks nothing is connected because the device draws very little power, or the phone is already full. Use the bank's low-current mode for earbuds and watches, or charge a phone at the same time to keep it awake.
Why is my power bank charging my phone so slowly?
USB-A ports and older banks often deliver only standard speed. Plug into the USB-C port marked PD with a USB-C cable, and make sure the bank isn't nearly empty, since some slow down at low charge.
Can a power bank damage my phone?
A working bank from a reputable brand won't. Your phone controls how much power it takes. Stop using any bank that's swollen, very hot or damaged.
Why does my magnetic power bank not charge through my case?
The case is likely too thick or has metal or cards in it. Wireless charging needs the bank close to the phone's coil. Use a slim case with built-in magnets or take the case off.