Common Causes and Fixes

  1. 1

    Use a wall outlet, not a computer USB port

    Standard USB-A ports on computers output only 0.5–0.9W. A phone charger wall outlet delivers 5–25W depending on the adapter. This is the most common cause of “slow charging” — the phone is charging fine, just from an underpowered source. Always charge from a mains wall outlet for full speed.

  2. 2

    Use the correct charger and a quality cable

    A cheap or incompatible cable is a very common slow-charging culprit. Cheap cables often have thin copper wires that limit current delivery. Use the original charger and cable that came with the phone, or a certified replacement (MFi-certified for iPhones, USB-IF certified for Android). The charger wattage must match what the phone supports — a 5W charger on a phone that supports 25W fast charging will be slow.

  3. 3

    Clean the charging port

    Lint and debris packed into the charging port prevents the cable from fully seating, reducing or preventing charging contact. Use a wooden toothpick or a soft toothbrush to gently remove compacted lint from the port. Do not use metal objects. After cleaning, check that the cable seats firmly with no wobble.

  4. 4

    Enable fast charging (if supported)

    Many Android phones have fast charging that can be accidentally disabled. Settings → Battery → look for Fast Charging, Adaptive Fast Charging or Super Fast Charging toggle — ensure it is enabled. iPhones support fast charging with an 18W+ USB-C adapter and USB-C to Lightning or USB-C to USB-C cable — the 5W adapter included with older iPhones is not fast charging.

  5. 5

    Stop using the phone while charging

    Screen-on usage, gaming and video streaming draw significant power while charging. Net charging rate = charging rate minus usage rate. Heavy usage while charging can result in the battery barely gaining charge or even losing charge despite being plugged in. Enable Aeroplane Mode while charging for maximum charge speed.

Battery degradation causes slow charging tooAn old, degraded battery charges slowly because its internal resistance has increased. iPhone: Settings → Battery → Battery Health → check the Maximum Capacity percentage. Below 80% is considered significantly degraded — battery replacement by Apple or an authorised repairer improves charging speed and battery life.

Frequently Asked Questions

Yes — wireless (Qi/MagSafe) charging is inherently less efficient than wired charging. Standard Qi charges at 5–15W; MagSafe charges iPhones at up to 15W. Wired fast charging can reach 25–120W on supported devices. For overnight charging, the speed difference is irrelevant. For a quick top-up before going out, wired charging is significantly faster. Wireless charging also generates more heat, which can slightly reduce long-term battery health.
Mild warmth during charging is normal. Excessive heat (uncomfortable to hold, or the phone warns you about temperature) is not. Remove any case while fast charging as cases trap heat. Avoid charging in direct sunlight or on soft surfaces. Do not use the phone for intensive tasks (gaming, navigation) while fast charging — the combination generates significant heat which slows charging and degrades battery health over time.