Screenwash is not the most glamorous accessory to buy for a car, but drive your car without it, and you’ll soon notice its absence. As you travel, dirt and muck build up on your windscreen, and just using the wipers alone won’t be terribly effective – plus, you run the risk of scratching your windscreen glass.
This is why screenwash is so important, especially during the winter months when damp, salt-treated road surfaces throw up a lot of muck that can surprisingly quickly restrict your view. Equally important, a good screenwash-to-water ratio in the reservoir can help prevent your washer fluid from freezing.
The best screenwash at a glance
And while it may be tempting to just pick up any old bottle of cheap screenwash from the supermarket petrol station, you can get a better product with far superior performance if you’re prepared to look around.
What is screenwash and why does it matter?
Screenwash (also known as windscreen wiper fluid or washer fluid) is a specially formulated fluid used in a vehicle’s washer system to help the wipers remove dirt, insects, salt, and road grime, ensuring clear visibility in all driving conditions.
The role of screenwash in safe driving: Screenwash is vital for a clear windscreen and good visibility as it improves wiper performance by preventing smears. It often contains an antifreeze to stay effective in winter.
Screenwash vs. water – why you shouldn’t just use tap water: Tap water might work in an emergency, but it’s no substitute for screenwash. It lacks the cleaning power to tackle insects and grime, it can freeze in cold weather, and it can clog washer jets with its natural mineral deposits. Screenwash is specially formulated to clean effectively, resist freezing, and protect your system.
How to choose the right screenwash for your needs
Seasonal screenwash: winter vs summer formulas
Winter screenwash: It contains antifreeze agents to prevent freezing in low temperatures (often down to -10deg C or lower). It cuts through road salt, slush, and greasy winter grime and is essential for winter driving.
Summer screenwash: This product focuses on removing bugs, pollen, dust, and traffic film. It has little or no antifreeze, so it’s often cheaper and tailored for warmer conditions.
Concentrated vs ready-mixed: which is better?
Concentrated: It must be diluted with water before use. They require less packaging, so concentrated products are more cost-effective and eco-friendly and they also allow you to adjust strength based on season or needs.
Ready-mixed: It’s pre-diluted and ready to pour, which makes it convenient and hassle-free. It’s usually a bit pricier per litre, but it’s ideal for quick top-ups, and the consistent formula means there are no mixing errors.
Which to choose? If you prefer convenience, go ready-mixed. For flexibility and value, concentrated is best.
Key ingredients to look for (and avoid)
Look for: Surfactants to break down grease, dirt, and bugs for effective cleaning. Alcohols will help prevent freezing and enhance cleaning power. Similarly, anti-freeze agents will protect against freezing in cold weather, and water conditioners will prevent mineral buildup and protect washer jets. If you have small children, it’s worth looking for a screenwash that contains Bitrex, the most bitter-tasting substance in the world, which is added to make the sometimes brightly coloured liquids extremely unpalatable and thus discourage accidental swallowing.
Avoid: Harsh acids or bleach, which can damage paint, rubber seals, and wiper blades. High concentrations of methanol can be toxic and potentially harmful if mishandled. Many modern screen washes avoid methanol due to its toxicity. And don’t trust your mate’s ‘homebrew mixture’. It might harm vehicle components, be toxic and be rubbish at cleaning your windscreen.
Is screenwash universal? Will it work in my car?
Yes, while most screenwash products are universal, some vehicle manufacturers may recommend or require specific formulations, especially for electric or hybrid vehicles, or those with advanced sensor systems. Always check your vehicle’s owner manual or manufacturer guidelines before choosing a screenwash, particularly if your car has unique features or warranty conditions. When in doubt, opt for high-quality, branded screenwash products that meet industry standards.
The best screenwash to buy 2025
Editor's choice
Pros
- Great value for money
- Great for the winter months
Cons
- That big bottle needs somewhere to live
Best ready to use screenwash
Pros
- Ready to use
- No dilution need
Cons
- Doesn't last as long as concentrate
The best concentrated screenwash
Pros
- Exceptional performance
- Quality product
Cons
- Don't forget to dilute
The best value screenwash
Pros
- Exceptional value for money
- Solid performer
Cons
- Huge bottle will make storage annoying
The best eco-friendly screenwash
Pros
- Eco-choice
- Leave it in your glovebox
Cons
- Takes a while to dissolve
The best rain repellent screen wash
Pros
- Year-round use
- Leaves a water-repellent film on windscreen
Cons
- Must be used neat in winter for best results
How much screenwash should you use?
If you’re using ready-mixed screenwash, simply pour it in until the bottle is empty or the reservoir is full. With concentrated screenwash, you’ll need to dilute it with water, and the ratio depends on the season. In summer, a mix of 1:10 or 1:20 (screenwash to water) is usually fine. In winter, stronger protection is needed, so ratios of 1:1 or even 2:1 are recommended, meaning equal parts or twice as much screenwash as water.
DIY tips for refilling without spills
The best tip is to use a funnel; it makes it so much easier. If you don’t have one, you can make a temporary funnel by cutting the bottom off a plastic bottle. Pouring slowly is another good practice, as this prevents water from splashing back. If you prefer, you might find it easier to transfer the fluid to a container with a pouring spout to give you more control. Below, we’ve put together a short video with Affiliate Operations Editor Adam Binnie to demonstrate how to top up screenwash.
How to top up screenwash
FAQs
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How often should you top it up?
It depends on vehicle use and driving conditions. In summer, a weekly check and a monthly top-up might be fine, whereas in winter, you might find you could use all your screenwash during a single motorway journey. Many modern cars have a low screenwash warning light - don’t ignore it, especially in poor weather
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Can screenwash freeze in the tank?
Yes, it is possible, especially if the temperature goes particularly low and the screenwash mix is weak. In winter, go with a 1:1 or even 2:1 ratio (screenwash to water) for proper freeze protection.
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Is screenwash a legal requirement in the UK?
While there’s no law that specifically says 'you must have screenwash,' the law does require that:
❝All vehicles must have a working windscreen washer system that can clean the windscreen.❞
— The Road Vehicles (Construction and Use) Regulations 1986
So, if your windscreen washer bottle is empty and you can't clean your screen, you’re breaking the law. -
Will it remove bugs, bird droppings, or tree sap?
A good quality screenwash should tackle bugs easily. Bird droppings may prove more difficult, especially if they have dried. Tree sap is sticky and resinous, and most standard screenwashes won’t be able to get rid of it effectively. You’ll probably need a glass cleaner or a bird poo remover and get to work on it with a microfibre cloth and a bit of elbow grease.
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Can you use any screenwash with rain-sensing wipers or heated jets?
Any good-quality screenwash is generally suitable for most vehicles with rain-sensing wipers and heated washer jets. In general, it's best to avoid additives that leave residues, as these can create films that interfere with sensor accuracy or clog heated jets. Smear-free formulas will help prevent streaks that might confuse sensors and cameras. It's always a good idea to check your manufacturer’s recommendations, as some specify particular screenwash types to ensure optimal sensor performance and avoid damage.
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How we choose
All of these screenwashes have been hand-selected by our team of experts, who have spent hours investigating and researching screenwash to make it easier for you to find the very best. We’d never recommend a product we don’t believe in. Where possible, we also test and share the latest and best products you should know about.
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