Symptoms
- Charging takes several hours to reach full
- Percentage barely moves after 30 minutes on the charger
- Phone charges fine on one charger but slowly on another
- Charging slows further while the phone is in use
Likely causes
- CommonLow-wattage or non-fast-charging adapterA basic 5W adapter charges far slower than a 20W+ USB-C power adapter.
- CommonUsing the phone while chargingActive screen use and apps draw power that competes with the incoming charge.
- PossibleWorn cable or dirty port limiting currentA degraded cable or debris in the port restricts how much power gets through.
- PossibleWireless charger below the phone's supported wattageBasic Qi pads charge slower than MagSafe or higher-wattage pads.
- Less commonBattery has aged and manages charging current more conservativelyOptimized Battery Charging can slow the final portion of a charge to protect battery health.
What to do
- Check the wall adapter's wattage; use a 20W or higher USB-C adapter for faster charging.
- Charge with the phone's screen off and apps closed rather than actively using it.
- Try a different Apple-certified cable to rule out a worn one.
- Clean the charging port of lint or debris.
- If using a wireless charger, confirm it supports at least 7.5W-15W for iPhone and is properly aligned.
- Disable Optimized Battery Charging temporarily (Settings > Battery > Battery Health & Charging) to see if speed improves overnight.
- Let the phone charge from a low percentage for 30 minutes and check how much it gained to gauge real speed.
- If speed stays low across multiple known-good chargers, consider a battery health check.
Tools and parts
20W or higher USB-C power adapterSearch: “20W USB-C fast charger iPhone”
When to call a pro
If a high-wattage adapter and good cable still charge slowly, have the battery and charging circuitry checked by Apple or an authorized repair shop.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.