Allow or Disable Wake Timers in Windows 10 & 11: See What Woke Your PC
If your PC goes to sleep fine but then turns itself back on a few minutes or hours later with nobody near it, a wake timer is almost always the reason. It's a scheduled task with explicit permission to pull Windows out of sleep at a specific time. Here's how to list what's armed, check what woke it last, and disable or restrict wake timers so it actually stays asleep.
Quick answer: Open Command Prompt or PowerShell as administrator and run powercfg /waketimers to see what's currently scheduled to wake your PC. To allow or block wake timers in Windows 10 or 11, go to Control Panel → Power Options → Change plan settings → Change advanced power settings → Sleep → Allow wake timers, and set it to Disable or Important Wake Timers Only (Enable lets every wake timer through). Read on for what each setting means, what woke it last time, the usual culprits, and why disabling wake timers completely can occasionally delay Windows Update.
What do the three "Allow wake timers" settings actually do?
The Allow wake timers option has three settings (on a laptop, there's one value for plugged in and another for battery):
- Disable — no wake timer can pull the PC out of sleep or hibernate, whatever a task asks for.
- Enable — when a wake timer expires, it wakes the PC from sleep or hibernate. That's how a task with "Wake the computer to run this task" ticked gets to run while you're away.
- Important Wake Timers Only — the middle setting. Windows lets through the wake timers it considers important and blocks the rest. Which ones count is Windows' call, and we couldn't find an official list. The example you'll see cited most is the restart Windows schedules after an update.
On Windows 11? It's the same place as Windows 10: the classic Power Options window, at Control Panel → Power Options → Change plan settings → Change advanced power settings → Sleep → Allow wake timers. Windows 11's Settings app (Settings → System → Power & battery) covers the screen and sleep timeouts, and this option isn't in that list. For those timeouts, see how to change the sleep timeout.
What a wake timer actually is
A wake timer is Windows' name for a scheduled task that's allowed to wake the PC from sleep at a specific time, regardless of whether anyone's touching the PC. It's different from a device wake source — a mouse, keyboard, or network adapter that wakes the PC in response to activity. A wake timer fires on a clock, not on input, which is exactly why it can wake your PC at 3 a.m. with nothing around it moving.
Task Scheduler is the mechanism. If a task has "Wake the computer to run this task" checked under its Conditions tab, a wake timer is registered for its next scheduled run. Most of them come from Windows itself — maintenance, Windows Update, disk checks — but backup software, antivirus scans, and some OEM utilities register their own too.
List what's armed right now
Open Command Prompt or PowerShell as administrator and run:
| Command | What it shows |
|---|---|
powercfg /waketimers | Every wake timer currently scheduled, and the task behind it |
powercfg /lastwake | What woke the PC the last time it actually happened |
powercfg /devicequery wake_armed | Devices (mice, network adapters) allowed to wake it from activity, not a timer |
powercfg /waketimers only lists timers that are currently scheduled — if a task already ran and woke the PC once, it won't show up here afterward unless it's set to repeat. If the list comes back empty but your PC still wakes itself up, the timer already fired and is waiting for its next occurrence, or the cause is a device wake source instead — check wake_armed next.
Find out what woke it last time
If you just want to know who woke it up overnight without waiting for it to happen again, powercfg /lastwake is faster than digging through Event Viewer. It names the exact process, driver, or wake timer responsible for the most recent wake — run it first thing in the morning and it'll usually point straight at the culprit.
Disable or restrict wake timers
The GUI path
Control Panel → Power Options → Change plan settings → Change advanced power settings → Sleep → Allow wake timers. There are three options: Enable (any wake timer can fire), Important Wake Timers Only (only the timers Windows treats as important), and Disable (nothing wakes the PC on a schedule, ever).
Best for: Most people — pick Important Wake Timers Only as a middle ground, or Disable if you never rely on scheduled backups or updates to run overnight. Note: Laptops and desktops set this independently for plugged-in vs. battery.
The command-line path
powercfg /setacvalueindex SCHEME_CURRENT SUB_SLEEP RTCWAKE 0 disables wake timers while plugged in; use /setdcvalueindex for battery. Index 0 is Disable, 1 is Enable, 2 is Important Wake Timers Only. Run powercfg /setactive SCHEME_CURRENT afterward so the change actually takes effect.
Best for: Scripting it once across multiple machines. Note: This changes the active power plan only — if you switch plans later, the setting doesn't follow.
The usual culprits
When powercfg /waketimers or /lastwake names something, it's almost always one of these:
- Windows Update — scheduled maintenance that wakes the PC to check for and install updates, then usually lets it go back to sleep.
- Scheduled tasks — anything in Task Scheduler with "Wake the computer to run this task" checked, including backup software and disk cleanup utilities.
- Automatic Maintenance — Windows' own daily maintenance window (Control Panel → Security and Maintenance → Automatic Maintenance), which is allowed to wake a sleeping PC by default.
If the PC wakes but doesn't go back to sleep afterward, that's a different problem — something is holding it awake once it's up. See why Windows won't go back to sleep and how to find what's blocking it.
Where PowerDoze fits in — and where it doesn't
To be upfront about it: PowerDoze doesn't disable wake timers. That's purely a Windows setting, and the steps under “Disable or restrict wake timers” are the real fix. What PowerDoze does is different — it schedules when the PC should sleep and which power mode it should be in at different times of day, so overnight the PC runs on a short, aggressive sleep timeout instead of whatever the default happens to be. If a wake timer does still fire and pull the machine up early, having it already in a low-power mode limits the damage instead of letting a full-performance profile run unattended until morning.
Honest note: If your PC is waking itself up, fix it with the steps under “Disable or restrict wake timers” — that's the actual cause. PowerDoze is for scheduling sleep behavior around the clock, not for controlling wake timers. Free for up to 3 time-based rules and 2 power modes, no account required.
Frequently asked questions
What is a wake timer in Windows?
A wake timer is permission Windows grants to a scheduled task or app to pull the PC out of sleep at a specific time, even with no one touching the keyboard or mouse. Task Scheduler, Windows Update, and disk maintenance are the usual sources. It's different from a device wake source like a mouse or network adapter — a wake timer is time-based, not activity-based.
How do I see what's scheduled to wake my PC?
Run powercfg /waketimers in an administrator Command Prompt or PowerShell. It lists every currently armed wake timer along with the task or driver that set it. If nothing is armed right now, it says so — a wake timer only shows up here while it's scheduled, not after it fires.
How do I check what woke my PC up last time?
Run powercfg /lastwake. It names the specific process, driver, or wake timer that pulled the machine out of sleep most recently — useful after a PC wakes itself up overnight and you want to know who did it, without waiting for it to happen again.
How do I disable wake timers in Windows 10 and 11?
Control Panel → Power Options → Change plan settings → Change advanced power settings → Sleep → Allow wake timers, then set it to Disable. From the command line: powercfg /setacvalueindex SCHEME_CURRENT SUB_SLEEP RTCWAKE 0 (plugged in) and powercfg /setdcvalueindex SCHEME_CURRENT SUB_SLEEP RTCWAKE 0 (battery), then powercfg /setactive SCHEME_CURRENT to apply it.
Where is Allow wake timers in Windows 11?
In the same classic window as Windows 10: Control Panel → Power Options → Change plan settings → Change advanced power settings → Sleep → Allow wake timers. Settings → System → Power & battery in Windows 11 covers the screen and sleep timeouts, and this option isn't in that list.
What does Important Wake Timers Only actually allow?
It's the middle setting between Enable and Disable. Windows still lets through the wake timers it considers important and blocks the rest. Which ones count as important is Windows' call, and we couldn't find an official list, so think of it as fewer wake-ups, not none. Disabling wake timers outright is the strictest option, and it can occasionally delay updates.
Can PowerDoze disable wake timers for me?
No — wake timers are a Windows setting, and PowerDoze doesn't touch them directly. What PowerDoze does is schedule when the PC should sleep and which power mode it should be in at different times of day, so if something does wake it early, it can drop back into a low-power mode automatically instead of staying fully awake until morning.
Wake timers sorted, but still want overnight sleep behavior to be smarter than one fixed timeout? Time-based rules are free, up to 3 rules and 2 power modes, no account required.
See also: Why Windows won't sleep · Change when Windows sleeps · Does Windows have a sleep timer? · All features