A
slow-charging MacBook can turn a quick power top-up into a frustrating wait.
While modern laptops are designed to charge efficiently, several factors—from
power sources to battery health—can significantly reduce charging speed. If
your MacBook used to charge faster but now takes hours to reach full capacity,
there’s likely an underlying issue that can be fixed. In this article, we’ll
explore the most common reasons for slow charging and provide practical
solutions to restore your MacBook’s charging speed.
1. Power Source Issues
Using Underpowered Chargers (e.g., iPhone Adapter)
One
of the most common reasons for slow charging is using a low-wattage power
adapter. While it’s tempting to plug your MacBook into an iPhone charger in a
pinch, these smaller adapters (typically 5W or 20W) simply don’t provide enough
power for a laptop. A MacBook Air requires at least a 30W charger, while a
MacBook Pro may need 60W or more for optimal charging. If you frequently use an
underpowered charger, your MacBook might still charge—but much more slowly,
especially if you’re using the laptop at the same time. Always check your
charger’s wattage (printed on the adapter) and ensure it matches or exceeds
your MacBook’s recommended power input.
Damaged or Wrong Wattage MagSafe/USB-C Cable
Even
if your power adapter is sufficient, a faulty or low-quality cable can
bottleneck charging speed. Frayed wires, loose connections, or non-certified
USB-C cables may not support fast charging. Apple’s original MagSafe and USB-C
cables are designed to handle the required power delivery, but third-party
cables without proper certification may fail to deliver full wattage. If your
MacBook charges normally with one cable but slowly with another, the cable is
likely the culprit. Inspect it for physical damage and replace it if necessary.
For USB-C charging, look for cables rated for at least 60W (or 100W for
high-performance MacBooks).
Unstable Power from USB Hubs or Docks
Many
users charge their MacBooks through USB-C hubs or docking stations for
convenience. However, not all hubs provide consistent power delivery. Some
cheaper models split power between connected devices, reducing the amount
available for charging. If your MacBook charges slowly when connected to a dock
but normally when plugged directly into the wall, the hub may be limiting power
output. To test this, bypass the hub and connect your charger directly to the
MacBook. If charging speed improves, consider using a higher-quality dock with
dedicated power pass-through or charging your laptop separately when fast
charging is needed.
2. Background Activity Drain
Your
MacBook prioritizes powering active tasks over charging the battery. If you’re
running demanding applications—such as video editing software, games, or
multiple browser tabs—your laptop may charge much slower because it’s diverting
energy to performance. Even background processes like software updates, cloud
backups, or antivirus scans can consume significant power. To check activity,
open Activity Monitor (Utilities folder) and sort by CPU or Energy Impact.
Close unnecessary apps and pause heavy tasks while charging.
3. Battery Health Factors
High Battery Cycle Count (Check System Report)
All
batteries degrade over time, and MacBooks are no exception. After hundreds of
charge cycles, your battery’s capacity diminishes, leading to slower charging
and shorter runtime. To check your battery health, go to Apple Menu > About
This Mac > System Report > Power and look at the "Cycle Count."
Most MacBook batteries are rated for 1,000 cycles before significant
degradation occurs. If your cycle count is high (e.g., over 800), your battery
may no longer hold a full charge, and charging speed can drop as the system
tries to preserve battery health.
macOS Throttling Degraded Batteries
To
prolong battery lifespan, macOS may intentionally slow charging when it detects
an aging or overheating battery. This safety feature prevents excessive wear
but can make charging take longer. If your MacBook consistently charges slowly
even with the correct charger and cable, check System Preferences > Battery
> Battery Health for warnings like "Service Recommended." If your
battery is degraded, recalibrating it (fully draining and recharging) might
help temporarily, but eventually, a replacement will be necessary for optimal
performance.
4. Temperature Effects
Lithium-ion
batteries charge most efficiently at room temperature (10°C to 35°C / 50°F to
95°F). If your MacBook is too hot (e.g., from direct sunlight or heavy use) or
too cold (left in a car in winter), charging may slow down or pause entirely to
prevent damage. To fix this, move your laptop to a cooler or warmer environment
and let it stabilize before charging. Avoid using your MacBook on soft surfaces
like beds or couches, which can block ventilation and cause overheating.
5. Software & Settings
Outdated macOS Affecting Power Management
Software
bugs in older macOS versions can interfere with charging efficiency. Apple
frequently releases updates to optimize power delivery and battery management.
Go to System Preferences > Software Update to install the latest macOS
version. If slow charging started after an update, check Apple’s support forums
for known issues. Occasionally, a subsequent patch may be needed to fix
power-related bugs.
Resetting SMC (System Management Controller)
The
SMC controls power management, including charging behavior. If your MacBook
charges inconsistently or too slowly, resetting the SMC can help. For Intel
Macs, shut down the laptop, plug in the charger, then press Control + Option +
Shift + Power for 10 seconds. For Apple Silicon Macs, simply restarting usually
resolves SMC-related issues. This reset clears temporary power glitches and
often restores normal charging speed.
6. When to Consider Replacement
If
you’ve tried all troubleshooting steps—using the correct charger, reducing
background activity, resetting the SMC—and your MacBook still charges slowly,
the battery or charging port may need replacement. Persistent issues,
especially with an older MacBook, suggest hardware wear that can’t be fixed via
software. Visit an Apple Store or authorized service provider for diagnostics.
Battery replacements are often affordable and can significantly improve
performance.
Conclusion
Slow
charging doesn’t always mean a failing MacBook—often, it’s a simple fix like
switching to a higher-wattage charger, closing energy-hungry apps, or updating
macOS. However, if your battery is aging or damaged, a replacement may be the
best solution. If you suspect your macbook charger
is the problem, consider upgrading to a reliable third-party option like
Anker’s USB-C chargers, which offer efficient power delivery and built-in
safety features. With the right adjustments, you can keep your MacBook charging
quickly and reliably for years to come.
