My iMac is making hourly Time Machine backups during sleep mode. How can I keep it from doing that?

Question

My iMac is making hourly Time Machine backups during sleep mode. How can I keep it from doing that?

My iMac is in my bedroom. I don't want to shut it down every night (it takes a long time to start up,) I just want it to go to sleep and do nothing. But it thinks it has to do hourly Time Machine backups in the middle of the night, and my wife is sensitive to the sound of the backup disk.

There used to be an option for Intel Macs to avoid that, by turning off the "Power nap" option. That's gone for Apple Silicon macs.

Any ideas? I know that I can shut down the computer every night or that I can just stop Time Machine from doing regular backups. But that's not what I want to do.

iMac 24″

Posted on Nov 23, 2025 12:49 PM

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Answer 1

Nov 23, 2025 1:19 PM in response to Christoph Drösser

You cannot do what you want to do using the settings, and only Apple can change that.

To have Apple consider your feedback, submit it here:

Feedback - macOS - Apple

As you noted, Power Nap is permanently on with Apple Silicon Macs. If you are ok using a pmset Terminal command, you can set hibernate mode 25. I suspect (but don't know for certain) that will block the sleeping backups.

https://www.intego.com/mac-security-blog/what-does-your-mac-do-when-its-sleeping/

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Answer 2

lkrupp

Level 7

22,105 points

Nov 23, 2025 1:28 PM in response to Christoph Drösser

See if this works for you. System Settings->General->Time Machine->Options->Backup Frequency->change to Automatically Every Day or Automatically Every Week.

This assumes your are running macOS Tahoe 26.1

Personally once per day is plenty for me.

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Answer 3

Nov 24, 2025 11:29 AM in response to Christoph Drösser

Christoph Drösser wrote:

My iMac is making hourly Time Machine backups during sleep mode. How can I keep it from doing that?

I see an interesting post here— related to your issue or not I am unclear...

ref: Working solution to hourly "DarkWake from… - Apple Community

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Answer 4

Nov 23, 2025 1:54 PM in response to lkrupp

lkrupp wrote:

Personally once per day is plenty for me.

FWIW, I set one of our Macs to once daily, and I suspect macOS thought it was being helpful by running that one backup in the middle of the night. That was Sequoia, I haven’t tried on Tahoe.

Depending on the size of the internal drive relative to budget, an SSD for backup is another potential solution.

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Answer 5

lkrupp

Level 7

22,105 points

Nov 24, 2025 5:15 AM in response to SergZak

Thanks for the additional information. Every bit helps.

I should also mention that there are third party ‘utilities’ floating around that provide scheduling of Time Machine backups. Buyer beware though.

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Answer 6

Nov 23, 2025 12:58 PM in response to Christoph Drösser

Open the Time Machine app, and disable the automatic back option. If that doesn't work, try to look for a more experienced person, as my advice pertains to my experiences.

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