Printer Troubleshooting

How to Fix Printer Streaks: Inkjet, Laser and Scanner Lines

Last reviewed · General guidance — steps vary by model and operating system

Streaks, lines and bands on printed pages have several quite different causes, and the fix depends on which one you have. A faint white line across an inkjet print, a dark vertical stripe down a laser print and a line that only appears on photocopies each point to a different part of the printer.

The most useful thing you can do first is look closely at the streak and work out what type it is. Section 1 shows you how. The sections after that cover inkjet printers, laser printers, and streaks that only appear when you copy or scan. Not every fix applies to every model, and some streaks are caused by worn parts that cleaning cannot fix.

When this guide applies

  • Horizontal white lines or bands across text and images (typical of inkjet printers).
  • Colours that look washed out, striped, or have one colour missing.
  • Dark or light vertical lines running the length of the page (typical of laser printers).
  • Grey smears, smudges or repeating marks at regular intervals.
  • Lines that appear only on copies or scans, not on documents printed from a computer.

Possible causes

Clogged inkjet nozzles
Dried ink blocks some of the tiny nozzles in the printhead, leaving thin gaps that show up as white lines or bands.
Low ink or toner
A nearly empty cartridge can deliver ink or toner unevenly, causing faded areas or streaks.
Printhead misalignment
After moving the printer or changing cartridges, misaligned heads can produce blurry text, doubled lines or banding.
Wrong paper or quality setting
Using a fast draft mode, or a paper type setting that does not match the paper loaded, can produce visible banding.
Worn or dirty laser parts
A scratched or worn drum, a dirty corona wire on some models, or a fuser problem can produce vertical lines and smears.
Dirty scanner glass
Dust, ink or correction fluid on the scanner glass or the automatic document feeder (ADF) strip causes lines on copies and scans only.

Safety first

  • Turn the printer off and let it cool before reaching inside a laser printer. The fuser unit can be very hot and may carry a warning label; do not touch it.
  • Keep toner off skin and clothing and avoid inhaling toner dust. If toner gets on your skin, wash it off with cool water; warm water can make it harder to remove.
  • Do not touch the drum surface, printhead nozzles, electrical contacts or the clear plastic encoder strip inside inkjet printers.
  • Only remove parts that your printer’s manual describes as user-removable.

1. Identify the type of streak

Spend a minute examining a printed page. The answers to these questions tell you which section to follow.

  1. Is it an inkjet or a laser printer?

    Inkjet printers use liquid ink in cartridges or refillable tanks. Laser printers use toner powder. If you are not sure, check the model name in the manual or on the manufacturer’s website. Inkjet printers: go to sections 2 to 4. Laser printers: section 5.

  2. Which direction does the line run?

    On inkjet printers, the printhead moves across the page, so blocked nozzles usually cause horizontal lines or bands running across the width of the page. On laser printers, the drum and rollers turn as the page passes, so defects usually cause vertical lines running from top to bottom.

  3. Is it a white gap or a dark mark?

    A white or light line usually means ink or toner is missing from that area. A dark line, smear or grey haze usually means extra toner or ink is reaching the page where it should not.

  4. Does it appear on copies only?

    Print the same document from a computer and make a copy of a clean page. If only the copy has the line, the printer is fine and the scanner glass needs cleaning: go to section 6.

  5. Does a mark repeat at regular intervals?

    On laser printers, a mark that repeats a set distance apart down the page often comes from a rotating part such as the drum or fuser. Some manufacturers publish a “repetitive defect” chart in the manual that matches the spacing to a specific part.

2. Inkjet: check ink levels and run a nozzle check

  1. Check the ink levels

    View the levels on the printer’s screen, in its companion app or in the driver software. On ink-tank printers, look at the tanks directly. Replace or refill any colour that is very low before doing anything else, because cleaning uses ink.

  2. Print a nozzle check or print-quality report

    This test page prints a pattern for each colour. It is usually found in the printer’s Maintenance, Tools or Print Quality menu, or in the driver’s maintenance tab on Windows or the printer utility on macOS. Menu names vary by model and brand.

  3. Read the pattern

    Look closely at each colour block or line grid. Gaps or broken lines in one colour mean that colour’s nozzles are blocked. A completely missing colour may mean an empty or unseated cartridge. If the pattern is perfect but your prints still have streaks, skip to section 4.

3. Inkjet: clean the printhead

Our dedicated guide on how to clean a printhead covers this in more depth. The short version:

  1. Run one cleaning cycle

    Start the printer’s Head Cleaning or Clean Printhead function from the control panel or driver software. Let it finish completely; do not turn the printer off during cleaning.

  2. Print another nozzle check

    Compare it with the first one. If it has improved but is not perfect, you can run another cycle. Many manufacturers advise a limited number of cycles in a row and suggest waiting before trying again; follow your manual.

  3. Avoid running cycles back to back

    Each cleaning cycle uses ink, which ends up in an internal waste ink pad or tank. Repeated cycles can use a lot of ink without improving a stubborn clog. If two or three cycles do not help, leave the printer switched on for several hours or overnight, then try again.

  4. Consider a deeper clean only if offered

    Some printers offer a “deep” or “power” cleaning option, which uses considerably more ink. Use it only if normal cleaning has not worked and your manual recommends it.

4. Inkjet: alignment, paper and quality settings

  1. Align the printhead

    Run the Printhead Alignment or Align Printhead function, usually in the same maintenance menu as the nozzle check. Alignment is especially useful after moving the printer or fitting new cartridges, and it often fixes fine banding, fuzzy text and doubled lines.

  2. Match the paper type setting

    In the print dialog, choose the paper type that matches what is in the tray, such as plain paper or a specific photo paper. The printer adjusts how much ink it uses and how the head moves based on this setting.

  3. Use a higher quality mode

    Draft or fast modes make fewer passes and can show banding, especially on photos and large areas of colour. Try the standard or high quality setting.

  4. Check the paper itself

    Printing on the wrong side of coated photo paper, or on damp or curled paper, can cause smearing and uneven ink. Load paper with the printable side facing the way the tray indicates.

  5. Consider the cartridges

    Streaks that started straight after changing cartridges may be linked to that cartridge. Reseat it first. If you use compatible or refilled cartridges, results can vary between products; trying a different cartridge, genuine or otherwise, helps show whether the cartridge is the cause.

5. Laser printer stripes: toner, drum, corona wire and fuser

  1. Check the toner level and redistribute

    Faint or light vertical streaks often appear as toner runs low. Turn the printer off, remove the toner cartridge and, if your manual allows it, rock it gently from side to side a few times to spread the toner evenly. Do not shake it hard and do not open it.

  2. Inspect the drum

    On models with a separate or built-in drum, look at the drum surface without touching it. Scratches, marks or a spot of debris can produce a line that runs the length of every page. Keep the drum out of bright light, and return it to the printer quickly. If the printer reports that the drum is near the end of its life, replacing it may be the fix.

  3. Clean the corona wire on models that have one

    Some laser printers, including many models with a separate drum unit, have a thin corona wire with a small sliding tab or cleaner on the drum. Sliding the tab gently from one end to the other and back several times, then returning it to its home position, can clear vertical streaks. Only do this if your manual describes it, and make sure the tab is returned to its home position or it may cause a new streak.

  4. Try a different toner cartridge

    A damaged or defective cartridge can cause consistent lines. Swapping in another cartridge, if you have one, helps narrow down the cause.

  5. Smears that rub off point to the fuser

    If toner on the page smudges easily when you rub it, or there are grey smears and repeating marks, the fuser unit may not be bonding toner properly. Check the paper type setting first, because heavy or coated paper needs a matching setting. The fuser is not usually a part for owners to handle; some business models have a user-replaceable fuser described in the manual.

  6. Run any built-in cleaning page

    Some laser printers have a cleaning mode or cleaning page function in their maintenance menu. Check your manual to see whether your model offers one.

6. Streaks on copies or scans only

When a line appears on copies or scanned images but not on documents printed from a computer, the cause is almost always the scanner.

  1. Clean the flatbed glass

    Turn the printer off. Lightly dampen a soft, lint-free cloth with water (or a non-abrasive glass cleaner, if the manual permits it) and wipe the glass. Never spray liquid directly onto the glass, because it can seep underneath. Dry it with a clean cloth.

  2. Clean the ADF scanning strip

    If the line only appears when you use the automatic document feeder, clean the narrow glass strip, usually to the left of the main glass, and the white plastic strip on the underside of the lid above it. A small speck of dust or correction fluid here causes a line along the whole page.

  3. Clean the underside of the lid

    Wipe the white backing on the underside of the scanner lid. Marks here can show up on copies of thin paper.

If it still isn’t working

Print regularly. Inkjet nozzles are more likely to dry out when the printer sits unused for weeks. Printing a page with all colours every week or so can help prevent streaks returning.

Use the manufacturer’s utility. Many brands include maintenance tools in their official apps and driver software. Download them only from the manufacturer’s official website or app store. Our printer brand pages explain where to look.

Replace worn consumables. On laser printers, drums and toner cartridges are designed to be replaced. On inkjets with the printhead built into the cartridge, a new cartridge also means a new printhead.

Know when to stop. If streaks continue after cleaning, alignment and fresh consumables, the printhead or another internal part may be worn or damaged. Check the manufacturer’s official support resources or your warranty before spending more on ink or parts.

Frequently asked questions

What causes streaky print on an inkjet compared with a laser printer?

On an inkjet, streaky print is usually horizontal banding caused by clogged or dry nozzles, low ink or a misaligned printhead. Laser printer stripes usually run down the page and point to the toner cartridge, the drum unit or, on some models, a dirty corona wire.

Why is my printer printing lines across the page?

On inkjet printers, horizontal lines are most often caused by partially blocked printhead nozzles, low ink or misalignment. A nozzle check shows whether nozzles are blocked; a cleaning cycle and alignment fix many cases.

Why does my laser printer have a vertical line on every page?

A vertical line on a laser printer usually comes from the drum, the toner cartridge or, on some models, a dirty corona wire. A mark that repeats at a set spacing often matches a specific rotating part.

How many times should I run head cleaning?

Follow your manual. As a general rule, run one cycle, check the result with a nozzle check, and stop after a few attempts. Running many cycles in a row uses a lot of ink and may not clear a stubborn clog.

Why do streaks only appear when I copy?

If computer printouts are clean but copies have lines, the scanner glass or the narrow ADF strip is dirty. Cleaning the glass usually removes the line.