Reviewed & Rated: The best screenwash tested

Unless your classic is very old, you’ll need to make sure there is some fluid available when you press the button to wash the windscreen. In winter it will help get rid of road grime and salt, in summer it helps clear fly splats, dust and diesel film.

No one likes having to pay service station prices for screenwash when you’ve run out mid-journey, and garages tend to charge through the nose for the precious fluid at a service too, so it makes sense to keep some in stock. But which is the best?

We tried seven different types, testing them for freeze resistance in winter conditions and cleaning ability at weaker summer concentrations.

To test the cold weather performance, we sucked up the fluids into syringes at the suggested mix rate and left them in a freezer for 12 hours, checking at intervals to see how quickly they froze.

We then mixed at the suggested summer concentration and checked the cleaning performance on a clean piece of glass using 50ml of liquid and a wiper blade to see if it shifted a 5ml splats of engine oil and a 1cm long smear of Pritt Stick, to simulate sticky bug remains.

Halfords -20 Concentrated Screenwash

Score: 9
Price: £5.49
Cost per litre mixed, summer/winter: £0.54/£1.37
Frozen at -18^oC: No
Contact: halfords.com

As you might expect, Halfords has a bewildering array of screenwash options in store – we counted seven own-brand products alone, most of which are also available in different pack sizes.

The company has opted to make the products look different by colour (and smell) coding them according to the temperature protection level. The -20C liquid we selected is green and ‘Citrus’ flavour.

The ready mix options seem a little expensive at first, with a five litre bottle of the -20 Citrus costing £8.99, so we opted for the concentrate which was a more reasonable-seeming £5.49 for two litres. At home we realised the ready mix is actually much better value, as the label recommends using the concentrate neat for the full -20C protection, meaning it would cost almost £14 for five litres. That seems a bit odd to us, as concentrate should be cheaper once mixed.

However, there was some good news. As we didn’t need the full -20C protection we economised and tried a few different concentrations to see how they fared in the freezer. A mix of 50/50 with water was still squirting after 12 hours at -18C, so it would seem Halfords is understating its performance.

At a summer mix rate of 4:1 the Halfords wash cleared both the glue and the oil after a few wipes, giving the best cleaning performance in the test.

Autoglym Ultimate Screenwash 500ml

Score: 7
Price: £4.99
Cost per litre mixed, summer/winter: £1 /£3.32
Frozen at -18^oC: Partially
Contact: autoglym.com

As you might expect from the well-known and respected brand like Autoglym, the screenwash did well in the cleaning tests – but it’s expensive to use at winter temperatures.

The instructions recommend it is used at the ‘optimum clean’ dilution ratio of 1:9, which stops freezing down to a claimed -3^oC.

In summer this makes it seem good value compared to some ready-mix rivals, but the advantage disappears in winter.

Used neat – if you could afford it – would mean the fluid would still flow at -45^oC, according to the makers. But as it would cost more than £30 to fill up the average washer bottle you would squirt sparingly.

As we knew our freezer was measured at 18C, we mixed at a ratio of 1.5:1 which should have given us protection down to 19.5C. However, although there was some liquid evident in the syringe it was too frozen to squirt until it had been out of the freezer for a few minutes.

Tesco Concentrated Screen Wash (& Tesco Ready To Use)

Score: 7
Price: £3.25
Cost per litre mixed, summer/winter: £0.33/£1.30
Frozen at -18^oC: Yes
Contact: tesco.com

Most Tesco stores seem to have screenwash stacked up on displays at the entrance, making it easy to pick a bottle up along with your weekly shop – if you remember.

It certainly seems to make financial sense if you do. There are usually two types on offer; ready mix or the concentrate. We tried both, but the results were almost identical so we’ve concentrated on the concentrate.

In summer, it makes up to 10 litres and give protection against freezing down to -2C. If you need to go any colder it’ll need to be used 1:1 or even neat. The instructions say this will remain fluid down to -10C, so unsurprisingly it was solid after a few hours in our freezer compartment.

The cleaning ability was adequate if not spectacular, clearing the oil but leaving a remnant of our glue. This means that the Tesco wash is good value, but you’ll need to use more of it to clean away screen grime and refill the reservoir more often.

Prestone Max Visibility Screen Wash

Score: 6
Price: £6
Cost per litre mixed, summer/winter: £1.20/£1.20
Frozen at -18^oC: Yes
Contact: tesco.com

Tesco offers this bright yellow Prestone-branded ready to use ‘winter’ screenwash at a reasonable £6, making it cheaper per litre than the own-brand concentrate if you want protection down to -10C, and you won’t need to mess around with measurements either.

It was frozen solid after a few hours in our freezer as would be expected, but thawed quickly and was usable after 20 minutes.

As it’s ready-mix we used it undiluted on the oil/glue cleaning test, which should have given it an advantage over the watery rivals. But the cleaning was strange – while it quickly dissolved the glue it seemed to struggle with the oil, leaving smears on the glass.

Wynn’s Super Concentrated Screen Wash 21+

Score: 5
Price: £3.18
Cost per litre mixed, summer/winter: £3.18/£6.36
Frozen at -18^oC: No
Contact: wynns.eu

The bottle of Wynns is the smallest here, yet it claims to be ‘Super Concentrated’ and offer protection down to -70C. In reality though, that headline figure of -70C is only if you use the Wynns neat, which is unlikely to be necessary in the UK.

We tried it at the suggested level for protection down to -22C and it was fine and fluid after several hours in the freezer, but at that mix ratio it would make little more than half a litre. In fact, the instructions only suggest diluting it by up to a factor of 3:1, which means one bottle would only make a litre of fluid. Since the average washer reservoir is three to four litres, that’s going to be expensive.

At the summer mix ratio the cleaning performance was adequate, clearing the oil and leaving a small residue of glue, but no smearing.

Other than taking up little space on a shelf, we can’t see any advantage in the Wynns unless you have deep pockets and an arctic expedition planned.

WCSIL Screen Wash Tablets

Score: 1
Price: £2.88 (for 5)
Cost per litre mixed, summer/winter: £0.18/£0.18
Frozen at -18^oC: Yes
Contact: amazon.co.uk

There’s no cheaper way we could find of making screenwash than this, except maybe putting a squirt of Fairy Liquid in the reservoir. But as with most things, you get what you pay for and the tablets seemed to do little more than colour the water .

The clues to the quality start with the amusingly bad packaging, labelled as “Concentraed effervescent tablet of wiper”. Ignoring the spelling for a moment, the tablet is designed to be plopped straight into the washer fluid reservoir, which may be tricky if there is a filter in place. It takes several hours to dissolve too, so you risk blocking the outlet if you need to squirt straight away.

There is little aroma, no foaming and the fluid turned to ice as soon as the temperature dipped below zero. In the cleaning test it left smears from the oil and had no more effect on the glue than plain water.

The results make it difficult to believe these tablets are much more than just dye, and to compound our frustration the liquid also seemed to stain our containers and give our hands a blue tinge.

Verdict

The Halfords wash gave the best cleaning performance and excellent freeze resistance at a reasonable price so takes the win here, but we’d recommend buying the ready mix rather than the concentrate as – bizarrely – it’s better value.

The runners up are tied on points, and neither is perfect. The Autoglym will clean more quickly but is more expensive and we were disappointed to see it freeze. The Tesco fluid can’t cope with severe cold and will take longer to clean away grime in summer, meaning you’ll have to fill the reservoir more often.