Is bio or non-bio laundry detergent better?Which? compares bio and non-bio detergents

02 April 2016

Laundry capsules

Which? tests reveal big difference between bio and non-bio detergents

Our most recent tests of laundry detergents revealed big differences between biological and non-biological detergents. Find out which is best for your laundry.

Which? tests a range of different types of laundry detergent - capsules, powder, and liquids and gels. For each test, we always compare bio and non-bio products from big name brands, such as Ariel, Persil and Fairy, and cheaper supermarket own-brands. 

Our tough lab tests reveal how well each detergent removes tough stains, including wine, chocolate, mud, grease and blood. This year, like many years before, we've seen big differences between the average test scores awarded to biological and non-biological detergents.

Just want to know which laundry detergent is best for your laundry and budget? Go straight to our full laundry detergent results.

Bio vs non-bio detergent

When we tested laundry capsules earlier this year, we found a 17 percentage point difference between the top and bottom scoring capsules - one being biological and the other non-bio.

We found a similar pattern with powders when we tested them last year. There was a 32 percentage point difference between the highest and lowest scoring. Again, one bio and the other non-bio.

Our previous liquids and gels test wasn't quite so clear cut, and we're waiting to hear from our lab with the results of the latest test. So make sure you keep an eye out for the results in the near future.

However, just because - on average - one type of detergent scores lower than the other, this doesn't mean that you can't buy good and bad versions of both types. So use the results of our tests to make sure you pick the best stain busters that will preserve your bright colours and keep your whites white, and avoid the worst.

Should you use bio or non-bio detergent?

We asked Which? members what type of laundry detergent they use (survey March 15, washing powder users):

  • 37% only use non-bio
  • 28% only use bio
  • 32% use both.

Some people believe that non-biological detergents are kinder to skin because they don't contain enzymes. You can find out whether there's any scientific evidence to back this up by reading our full advice on biological and non-biological detergent, including what ingredients can target stains, in our guide to biological and non-biological detergents.

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