Does Your Alarm Work in Battery Saver Mode?

Your alarm usually works in battery saver mode if it's the phone's own Clock app. Battery saver modes pause other apps, though, and an alarm app you've installed can be stopped by an extreme or ultra power saving mode. Use Beyond Alarm, which sets real alarm-clock alarms Android lets through, and add it to your saver's allowed apps.

The short version:

• Install Beyond Alarm. On Android every alarm is scheduled as a true alarm clock, and its reliability screen checks battery optimisation and the other settings that stop alarms, then opens each one to fix.
• Standard battery saver mainly limits background work. Extreme, ultra or maximum modes pause most apps outright.
• On a Pixel, add your alarm app to Extreme Battery Saver → Essential apps.
• On a Samsung, add it to Never sleeping apps as well.
• On an iPhone, Low Power Mode's list of limits doesn't include alarms.
• Your phone may switch a saver on by itself at low battery. Test with it on, or charge overnight.

Which battery mode are you using?

The word "battery saver" covers several very different things. The quick answer depends on which one was on when your alarm was due.

The pattern is the same everywhere: the stronger the mode, the shorter the list of apps it leaves alone. Your Clock app is almost always on that list. A downloaded alarm app often isn't until you add it.

What Android's own power saving lets through

Under every phone maker's battery screen sits Android's Doze, which kicks in when the phone is unplugged, still and dark, which is your bedside table all night. Google's Doze documentation says it "defers background CPU and network activity" and pushes standard alarms to a later maintenance window.

It also makes one clear exception: alarms set with setAlarmClock() "continue to fire normally", and "the system exits Doze shortly before those alarms fire." That is the method a real alarm clock should use.

Beyond Alarm uses it. In our Android code, every alarm, snoozes included, is scheduled with setAlarmClock rather than as an ordinary background job, so Doze itself doesn't delay it. The risk that's left is a maker's own battery manager or an ultra mode closing the app first, which is what the reliability screen is for.

On a Google Pixel

Google's page on using Battery Saver on a Pixel separates the two modes:

• Battery Saver: "Apps don't run in the background, unless you turn off battery optimization."
• Extreme Battery Saver: pauses most apps, slows the processor and cuts the screen timeout. "Phone, Messages, Clock, and Settings" keep running.

If you use a different alarm app, it must be on the list too. Go to Settings → Battery → Battery Saver → Extreme Battery Saver → Essential apps and turn it on. Google also notes "paused apps won't send notifications", so a paused alarm app stays silent.

Google's Clock even reports this after the fact. Its help page lists the notice "Battery Saver may have prevented your alarm from going off", and the fix it gives is to "turn off Battery Saver or add Clock as an essential app". For everything else on a Pixel, see the Pixel checklist.

On a Samsung Galaxy

Samsung's page on Power saving mode describes it as "reducing background activity and limiting certain features". Limit apps and Home screen turns it into Maximum power saving, with "additional restrictions to apps and features".

The bigger risk on a Samsung is a separate feature. Samsung's developer documentation on app management says that for sleeping apps, "features such as Job, Alarm, and Foreground-service are restricted". An alarm app you never open is exactly the sort that gets put to sleep.

1. Open Settings → Battery → Background usage limits (on some versions, under Device care).
2. Tap Never sleeping apps and add your alarm app.
3. If you use Maximum power saving at night, add the app on its allowed apps screen as well, then test.

Beyond Alarm adds a Never sleeping apps row to its reliability screen on Samsung phones, because no app can read that list for you. More Samsung causes are in the Samsung checklist.

On Xiaomi, OPPO, realme, vivo and others

These makers add their own ultra or super power saving mode on top of the standard one. It shrinks the phone down to a handful of apps, and names and menus change between versions.

The test is the only reliable answer: switch the mode on, set an alarm for three minutes ahead, lock the phone and wait. If it doesn't ring, look in the mode's own settings for a list of allowed apps. Our brand guides cover the rest, from Xiaomi's per-app Battery saver to OPPO and realme's Super power saving mode.

On iPhone: Low Power Mode

Apple's Low Power Mode page says it "reduces background activity to extend battery life" and lists what it changes: Auto-Lock, brightness, visual effects, iCloud Photos, automatic downloads, email fetch and Background App Refresh. Alarms aren't on that list.

Beyond Alarm on iPhone (iOS 26.1 and later) sets every alarm through Apple's AlarmKit, so it rings on the lock screen the way the Clock app does. If an iPhone alarm went quiet, the cause is almost always elsewhere. Our iPhone guide goes through the nine settings to check.

The mode you didn't turn on

Many people say "I never use battery saver". But a phone can switch it on for you. On a Pixel, Schedule and reminders can turn Battery Saver on at a set percentage, and other makers have their own automatic triggers.

So a phone on 15% at midnight may spend the night in a saver mode you never chose. Two fixes: exempt the alarm app as above, or plug it in. Google's page notes Battery Saver turns off while the phone is charging.

How Beyond Alarm handles a battery-hungry phone

We built Beyond Alarm on the assumption that the phone will try to save power at the worst moment. On Android:

• Alarm-clock scheduling. Every alarm goes through setAlarmClock, the path Doze lets through on time.
• A reliability screen. It checks Exact alarm, Notifications, Full-screen alarm, Battery optimization and Alarm volume, adds Auto-start and "Don't pause if unused" on stricter makers, and Never sleeping apps on Samsung. Each row opens the right settings page.
• Restarts covered. Alarms are set again before you unlock the phone for the first time after a restart.
• A missed-alarm card. If an alarm came due and never rang, the home screen says so the next time you open the app, and links to the settings that fix it.

Test it tonight

Switch on the exact mode you sleep with. Set an alarm for three minutes from now, lock the phone, put it face down and walk away.

If it rings, you're covered. If it doesn't, exempt the app and test again. And if nothing rang at all for a reason that isn't battery, why an alarm didn't go off covers the other causes.

Sources

Checked on 13 November 2026.

• Android Developers: Optimize for Doze and App Standby
• Google Pixel Help: Use Battery Saver on a Pixel phone
• Android Help: Clock app alarm notices
• Samsung Support: What is Power saving mode on my Galaxy phone?
• Samsung Developers: App management
• Apple Support: Use Low Power Mode to save battery life on your iPhone