Green Line on Phone Screen: Causes, Fixes and Warranty Options

One morning there’s a thin, bright stripe running from the top of the display to the bottom, and a restart doesn’t touch it. A green line on a phone screen turns up on Samsung Galaxy phones, OnePlus, Pixel and iPhone alike, and on brand-new phones as easily as old ones.

It’s almost always hardware. But check that in 30 seconds first, because it decides whether you need a repair and who pays for it.

Thirty seconds to tell hardware from software

1. Take a screenshot and open it on another phone or a computer. If the line isn’t in the image, the fault is in the display itself, not in what the phone is drawing.
2. Restart and watch the boot logo. A line visible on the manufacturer logo, before Android or iOS has even loaded, is hardware.
3. Open a plain white, grey and black image. A line that looks the same on every colour points to a stuck column of pixels.
4. Press gently near the line on the frame, not the glass. If it flickers, changes or vanishes, a loose or damaged flex connection is likely.

If the line does show in screenshots, it’s a software or app problem. That’s rare, and an update or closing the app that shows it usually sorts it.

Why a single column of pixels goes green

Nearly every modern phone has an OLED (or AMOLED) panel. Each pixel is driven by tiny transistors and fed through thin data lines that run in columns across the display. Those columns reach the main board through a flexible ribbon, the flex cable, and a display driver chip.

When one column’s connection fails, because of a cracked trace, a weak bond at the panel edge, moisture under the seal or a driver fault, every pixel in that column gets stuck on one colour. Green is the most common because of how OLED subpixels are arranged and driven. The same fault can show as a pink line on the screen, a white line, a purple band or a cluster of lines.

What sets it off:

• Bonding or sealing defects in the panel, which can surface weeks or years after manufacture.
• Heat and humidity slowly weakening the edge bond.
• A drop or pressure, even one that left no visible crack, stressing the flex cable or panel edge.
• Liquid, which corrodes connectors over time.
• A poor-quality replacement screen from an earlier repair.

It appeared right after an update

A lot of owners first spot the line just after installing an update, so the update takes the blame. In April 2024 TechRadar reported Galaxy owners, including people with the S21 Ultra and S21 FE, saying green lines appeared after One UI 6.0 or the April 2024 security update. Samsung told affected users to visit an authorised Samsung service centre. TechRadar itself doubted software was the cause and thought overheating or damage to the display connection more likely.

The same year, PhoneArena covered reports of a thin green line on brand-new Galaxy S24 Ultra units shortly after launch. It noted the problem mainly affects AMOLED screens and can show in other colours, and it reached the same conclusion repair technicians do: replacing the display is the only fix that always works.

So why does an update seem to trigger it? Installing one means a restart, a phone that runs warm while it installs and optimises apps, and new display driver settings. If a panel connection was already marginal, that’s the moment it gives up. The update exposes the fault. It rarely creates it.

Worth trying before you book a repair

None of this will mend a failed panel. It rules out the rare software cases so you don’t pay for a repair you didn’t need.

1. Force restart. iPhone: press and release Volume Up, then Volume Down, then hold the Side button until the Apple logo appears. Samsung: hold Side and Volume Down for about 10 seconds. Pixel: hold Power and Volume Up for several seconds.
2. Install pending updates. iPhone: Settings › General › Software Update. Samsung: Settings › Software update › Download and install. Pixel: Settings › System › Software updates.
3. Test with a lower refresh rate. Samsung: Settings › Display › Motion smoothness › Standard. Pixel: Settings › Display › Smooth Display off. iPhone: Settings › Accessibility › Motion › Limit Frame Rate. If flicker stops, tell support.
4. Boot into Safe Mode on Android. If the line is still there, it isn’t an app overlay.
5. Run the built-in display test. On Samsung, dial *#0*# and use the Red, Green, Blue and Black tests, or go to Samsung Members › Support › Phone diagnostics. Other brands are in our Android diagnostic codes list.
6. Back up now. Lines often spread, or the screen goes black altogether.

What each brand does about it

Samsung Galaxy. Green lines have been reported across many generations, from the Note20 and S20 to S22 series through to the S24 Ultra. Samsung’s official advice is an authorised service centre. Inside the standard manufacturer warranty, a display defect with no physical or liquid damage is normally repaired free; outside it, you pay for the screen. Check coverage first with our Samsung warranty check guide or a Samsung Info report, which shows model, region and warranty data for the IMEI.

OnePlus. OnePlus has been the most open about it. In December 2024 OnePlus India announced a lifetime warranty against the green line problem on its smartphone displays, new and old, as part of what it called a “Green Line Worry-Free Solution”. It said it now uses a PVX edge-bonding layer in its AMOLED displays and runs extended “double 85” tests (85°C and 85% humidity). The announcement came from OnePlus India, so owners elsewhere should ask local OnePlus support what applies to them.

Google Pixel and iPhone. Owners report single coloured lines here too, usually after a drop or on an older panel. Neither Google nor Apple runs a public green-line programme, so normal warranty rules apply: a defect without damage is covered under warranty or AppleCare, and accidental damage usually means a service fee. An iPhone warranty check tells you whether yours is still covered before you book.

Spotting a green line on a used phone

They’re easy to miss on a busy wallpaper or a dark lock screen. When you inspect a second-hand phone:

• Open a plain white and a mid-grey image at full brightness and look across the whole width.
• Do it again at low brightness, where faint lines and tint bands show up better.
• Run the manufacturer’s display test (*#0*# on Galaxy phones).
• On an iPhone, look in Settings › General › About › Parts and Service History for a non-genuine or unknown display. Our guide to checking for original screen parts covers Android as well.
• Run a GSMA blacklist check and confirm the model with a manufacturer and model check, so a cheap faulty phone isn’t a blocked one too.

Claiming the screen under warranty

Before you go, get the IMEI (dial *#06#) and run a free All-in-one Basic Info check to confirm the exact model and warranty status. Our guide to checking phone warranty by IMEI or serial explains each result. Take along the screenshots that don’t show the line. They’re simple proof the fault is in the hardware.