Why are my wipers smearing?
What we would buy
- BoschAerotwin A864S flat blade set, 650/450 mm
Flat blade pair at 650/450 mm. Check your car's sizes first; the right length matters more than the brand.
Bosch Aerotwin A864S flat blade set, 650/450 mm: see the price on Amazon →
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Read the smear pattern
- Both directions: worn or dirty blades, a dirty windscreen, or contaminated or watered-down washer fluid.
- One direction only: blades that are too hard or the wrong size. Cleaning will not fix this; replace them.
- A clear line left unwiped: a split or torn rubber edge, or a blade that no longer presses evenly on the glass.
- Greasy haze after washing the car: wax or a cleaning product that has migrated onto the glass.
Free checks before you buy anything
- Clean the windscreen with a glass cleaner, then again with plain water, so no cleaner residue is left.
- Lift each wiper and wipe the rubber edge with a damp cloth until the cloth comes away clean.
- Check the washer fluid: use a proper screenwash at the dilution on the bottle, not plain water.
- If the jets spray unevenly, clear the nozzles with a pin, taking care not to change where they aim.
- Run the wipers on a wet screen. If the smears are gone, the blades were just dirty.
When to replace the blades
If the smear is still there after cleaning, or the rubber is cracked, split or no longer flexible, replace the blades. Sun and frost harden the rubber over time, which is why blades that look fine can still streak.
Buy the lengths your car takes, not the lengths of the blades you happen to have: our size chart lists the driver, passenger and rear sizes for 45 UK cars.
If new blades still smear
Contamination on the glass is the usual cause. A deep clean of the glass, then a rain repellent if you like the effect, often clears it. If one side keeps smearing with new blades, the arm may not hold the blade square to the glass: see our page on juddering wipers for the arm check.
Where to buy
Prime members get free delivery on eligible items: try Amazon Prime free.
Frequently asked questions
Why do my wipers smear only when it rains lightly?
Light rain spreads road film rather than washing it away. Clean the glass properly and use screenwash; if it persists, the rubber is probably hardened.
Can I just replace the rubber?
Some blades take refills, but most modern flat blades are sold as a complete blade. A complete blade also restores even pressure along the glass.
Does a rain repellent stop smearing?
It can help water bead and run off, but it will not fix worn blades, and some coatings can make old blades judder. Start with clean glass and good blades.