How to Fix MacBook Battery Draining During Sleep Mode

Closing the lid of your MacBook should place the machine into a deep low-power sleep state that preserves battery charge for days. However, many Mac users open their laptop in the morning only to discover that the battery has dropped by 20%, 40%, or completely depleted overnight while sleeping in their backpack.

When a MacBook drains battery during sleep, the hardware is not remaining truly dormant. Background maintenance processes, network wakeups (Bonjour sleeps), Find My location broadcasts, or connected Bluetooth accessories frequently trigger repeated wake cycles. This guide details how to diagnose background sleep assertions and configure power settings to ensure your MacBook retains its charge while sleeping.

Method 1: Identify Background Processes Preventing Deep Sleep

macOS includes a diagnostic command line utility named pmset (Power Management Settings) that reveals which applications or system services are holding active “sleep assertions”.

1. Press Command + Space to open Spotlight, type Terminal, and press Enter.
2. Type the following command to inspect active sleep-blocking processes:

   pmset -g assertions

3. Look at the output under the section labelled Listed by owning process.
4. Look for lines indicating PreventUserIdleSystemSleep or PreventSystemSleep set to 1.
5. Common culprits include cloud storage utilities (Dropbox, OneDrive), torrent clients, media players, or backup tools. If a background app is preventing sleep, quit the application before closing your laptop lid.

Method 2: Turn Off “Wake for Network Access”

The “Wake for network access” feature (historically called Wake on LAN) enables your Mac to wake up periodically when another Apple device or your Wi-Fi router requests shared printer, file, or photo library services.

1. Click the Apple menu in the top-left corner of the screen and select System Settings.
2. In the left sidebar, click Battery.
3. Scroll to the bottom of the Battery panel and click the Options button.
4. Find the setting titled Wake for network access.
5. Click the drop-down menu and change it from Always to Only on Power Adapter (or Never).
6. Click Done. Your MacBook will no longer wake from sleep due to network broadcasts when running on battery.

Method 3: Disable Bluetooth Devices Waking Your Mac

If you leave wireless Bluetooth mice, keyboards, or AirPods near your MacBook, accidental clicks or slight movement can wake the laptop from sleep inside a bag or on your desk.

1. Open System Settings from the Apple menu.
2. Click Bluetooth in the sidebar.
3. If you use external Bluetooth peripherals on a desk, ensure you toggle them off when packing your MacBook into a bag.
4. Alternatively, open Terminal and disable Bluetooth waking on battery with this command:

   sudo pmset -b ttyskeepawake 0

5. Enter your macOS administrator password when prompted.

Method 4: Optimise Sleep Hibernation Delays via Terminal

On Apple Silicon and modern Intel MacBooks, macOS uses a hybrid sleep mode (hibernatemode 3). In this state, RAM remains powered for quick wakeups. If your battery drains rapidly, you can instruct macOS to transition into deep hibernation (standby) much faster.

1. Open Terminal.
2. Check your current standby delay:

   pmset -g | grep standbydelay

3. Configure your MacBook to enter deep standby after 15 minutes (900 seconds) of sleep instead of waiting several hours:

   sudo pmset -b standbydelayhigh 900 standbydelaylow 900

4. Disable TCP keepalive packets from waking the machine during sleep on battery:

   sudo pmset -b tcpkeepalive 0

   Note: Disabling tcpkeepalive means Find My Mac updates and incoming FaceTime notifications will pause until you open the lid.

MacBook Sleep Power Settings Reference

The table below provides a quick reference for the primary power management settings that control MacBook sleep behaviour:

Setting	Terminal Property	Recommended Battery Value	Effect on Battery Life
Wake for Network Access	womp	0 (Disabled)	Eliminates periodic Wi-Fi packet wakeups
Standby Delay	standbydelayhigh	900 (15 mins)	Saves RAM state to SSD and cuts standby power
TCP Keepalive	tcpkeepalive	0 (Disabled)	Stops background mail and notification sync
Proximity Wake	proximitywake	0 (Disabled)	Stops nearby iPhones/Apple Watches waking Mac

Restoring Reliable Overnight Battery Life

By preventing network wakeups and shortening the transition into deep standby, your MacBook will consume less than 1% to 2% of battery life overnight. If battery loss persists after adjusting these settings, inspect your battery health under System Settings > Battery to confirm that normal physical cell degradation is not causing rapid voltage discharge.