- Lines after a drop = physical damage to the display — needs a screen replacement
- Lines with no drop = loose display connector or failing display — bring it in
- Flickering lines = sometimes a software issue first — try a restart
- Lines almost always get worse over time, not better
- The screen is still replaceable — walk in for a free diagnosis
What’s actually causing the lines?
Modern phone screens are made up of millions of tiny pixels arranged in rows and columns. When you see lines, it means a row or column of pixels has stopped receiving a signal — or is receiving a corrupted one. This happens for a few reasons:
The most common cause. A drop or impact can damage the LCD or OLED layer underneath the glass — even when the glass itself looks fine. The display panel is fragile and can crack internally without any visible crack on the surface. This shows up as lines, colour blotches, or dark patches spreading from a point of impact.
The display connects to the phone’s motherboard via a ribbon cable and connector. If this becomes loose — from a knock, a previous repair, or general wear — you can get flickering lines or partial display failures. This is sometimes fixable without a full screen replacement.
Rare, but possible — especially if the lines appeared after an update and there was no drop. A corrupted display driver or software glitch can occasionally cause flickering or distorted output. Try a restart first. If the lines disappear after a restart, it was software. If they come back, it’s hardware.
Leaving a phone in direct sunlight or in a hot car can cause the display to delaminate or develop dead pixel lines. Sitting on the phone or putting it in a tight back pocket with pressure can also cause internal display damage without visible cracking.
Try this first: restart your phone
Before anything else, do a full restart. If the lines appeared suddenly with no physical cause, a software glitch is the only scenario where this might actually fix it. Power the phone fully off, leave it a few seconds, and power back on.
If the lines are gone: keep an eye on it. If they come back, bring the phone in — an intermittent fault like that will become permanent. If the restart made no difference, the cause is hardware and you need a screen replacement.
Will the lines get worse?
Almost always, yes. Display damage is progressive. What starts as one thin line usually spreads over days or weeks into:
- More lines appearing across the screen
- Dark patches or ink-blot spreading outward from the damaged area
- Sections of the touchscreen stopping working
- The entire display going black while the phone still works
If any part of your touchscreen has become unresponsive alongside the lines, the damage is spreading. A screen replacement now costs significantly less than if you wait until the display fails completely. It’s still exactly the same repair — it just gets harder to use the phone in the meantime.
Can lines on a phone screen be fixed?
Yes — in the vast majority of cases. Lines are caused by a damaged display panel, and the panel is replaceable. The phone itself (the motherboard, the battery, your data) is almost always fine. A screen replacement sorts it completely.
The only exception is if the damage has spread to the motherboard — which is rare and usually only happens if the phone was severely crushed. Walk in and we’ll tell you within 2 minutes whether it’s a straightforward screen replacement or something more involved.
iPhone vs Samsung — is there a difference?
The cause is the same on both, but the display technology differs:
Uses OLED (iPhone X and later) or LCD (older models). Lines on OLED screens can appear green, white or as coloured vertical streaks. Screen replacement restores normal display.
Uses AMOLED displays. Damage often shows as a pink or green line, or a black spreading patch. AMOLED panels are replaceable same day on most Galaxy models.
Got lines on your screen? Walk in for a free look.
We’ll check it in 2 minutes and tell you exactly what’s going on — no charge, no obligation. Most screen replacements done the same day. Clapham Junction, open 7 days.