Persistent horizontal lines appear on iMac screen

Mine has started doing it today as well! Also 24" iMac purchased July 2021, so have had it around 4 years. My previous 2 iMacs lasted around 7 years each and were still working, only replaced them due to needing something speedier.

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My company is a huge Apple user, and their lack of a resolution to cover the replacement or repair of the M1 iMac screens which are clearly a defect is making us consider another vendor for our hardware going forward.

What makes you think I'm on Apple's side?

I just posted the facts about Apple Engineers not being in these forums and when to "complain"/report your problem. Remember the squeaky wheel gets the grease.

You got into a situation but don't shoot the messenger.

iMac Feedback was no help to me. I was even told that someone would get back to me with a solution! That never happened. I love Apple products. I have been using all of them for years. This issue with a computer that was barely one year old is extremely disappointing. Apple MUST come up with a solution, as it seems to affect thousands of users. Come on, Apple. I mean, come on.

Hi everyone. I've decided i'm not buying a new Apple product until Apple make on this problem what it's correct, because they know that this is an hardware design problem and nothing else.

So Apple must organize a service for everyone affected.

Waiting.

My iMac, purchased at the beginning of 2022, started this issue out of nowhere today. Ran through all the possible checks provided online before I came across this thread. Posting to make sure Apple knows that there are so many of us out here who have been sold the same defective product with little to no solution.

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Hi Apple Community,

As a loyal Apple user for 15+ years from Colombia, my family and team have always chosen Apple for our computers, iPads, iPhones, and Apple Watches. We deeply appreciate Apple's exceptional quality and customer service.

The Issue: I'm experiencing persistent horizontal lines on my iMac 24" screen - a problem affecting thousands of users worldwide. The external display works perfectly, confirming it's an internal display issue.

Our Request: Given the widespread nature of this problem, we respectfully ask Apple to:

• Investigate this as a potential manufacturing defect
• Implement a quality policy for affected iMac 24" users
• Offer complimentary repairs for documented cases

We've seen successful free repairs in this community, which gives us hope for a similar resolution.

We remain big Apple fans and trust in Apple's commitment to quality and customer satisfaction. This would be a great opportunity to demonstrate why Apple continues to lead in innovation and service.

Thank you for considering our request.

Best regards, A loyal Apple user from Colombia 🇨🇴

I have a group of people (72) on Chinese social media who has this issue, still adding ... this is not a case to be ignore, please united to solve this problem together apple users!

It costs almost 5000yuan in China to replace the screen, even I choose to replace this, then I will be afraid this screen will have the same issue. Right?

How should we do this ? any heads up? an idea to reach the top and rise their awareness? and give us a good solution.

"It costs almost 5000yuan in China to replace the screen, even I choose

to replace this, then I will be afraid this screen will have the same

issue. Right? "

While I can't promise, it seems that newer screens don't have the issue. We haven't heard about it on newer iMacs.

Same thing is happening to my Mac. And it gets really hot on a very small portion of left part of the screen. Bought Feb 2022. Just updated to the latest OS. Problem persists. Already sent apple feedback. So many people experiencing the same problem. Really hope apple does something to fix it.

Apple auto-emailed me, inc:

Congrats docmartinhk! At the time of this email, your reply was upvoted for the first time:

[quoted my comment]

And the thread was viewed 91829 times. This means that you helped both the person who voted on your reply as well as everyone who viewed the thread.

• actually, only "helped" by letting others know another has this problem, and showing Apple Store this thread and posts likely won't help with getting display replaced without full payment. Which is not really helpful.
• 
  
• And having so many views, seems to indicate a real issue; it's not the only thread on this either.

The best way to get information and answers is to call Apple Support. These forums will not solicit a direct response from Apple. Apple.com and support page will show the number to call for your region.

Happening the same to me. I was working on my M1 (2021) iMac when out of a sudden the horizontal lines appeared flickering in the bottom of my screen, and they are remained there since, covering the dock.

I've hit the Me Too, and sent Apple a report... i hope they do something!

Same problem for me. Today I used the computer for an hour in the morning then looked at my screen's wallpaper, noticed the image was pixelated. Very odd. Hadn't seen that before. Restarted the computer, then this problem started - on the lower 1/3 of my screen, with a little bit of flickering. Bought my M1 iMac 2021.7.24, always turn on air conditioning & or a small portable fan behind the screen if I notice the cord getting hot. I haven't noticed a hot screen like other people on this thread.

I have had the same issue starting September 28 2025.

I took my M1 iMac into the genius bar and left it for inspection. It has always been in a dry, dust-free environment in my small office without issues. I was told it would be $550 or so for repairs and perhaps another $90 in labor. I can't use my business mac like this, and the use of another monitor has made my eyes worse in the past two weeks. Photos attached.

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