the difference between bio and non-bio ?

It’s the question we are asked most often. What’s the difference between bio and non-bio? And luckily, it’s one we LOVE to answer so read on…


Bio laundry detergent contains enzymes. These are naturally occurring ingredients that help to break down common stains, such as food, sweat, blood, grass and grease. Enzymes have names like Amylase, Cellulase and Mannanase and they are really effective at digesting down proteins, oils and starches (that make up everyday stains) and lifting them from your clothes.

Bio detergent is best used in mid to low temperature washes (ideally between 20-40°C) as anything hotter can denature the enzymes, causing them to not work as effectively against stains. They prefer to work at body temperatures!

Our bio capsules are the green ones in case you were wondering, and they have incredible stain removal properties, earning us a recommendation from The Good Housekeeping Institute amongst many others.

If you don’t have excessively sensitive skin and you like washing on cooler temperatures, we’d recommend our smol bio. They’re great at stain removal, contain lower chemical concentrations than the big brands, are vegan and cruelty free and are posted through your letterbox as and when you need them.


Non-bio laundry detergent, on the other hand, does not contain enzymes and is popular with  those who have very sensitive skin.

Although non-bio does not contain stain-removing enzymes, it can still be great at removing stains and keeping your clothes clean and smelling fresh. You will probably find you just need to use slightly higher temperatures or longer wash cycles to aid the cleaning process.

If you have sensitive skin (contact dermatitis, eczema, psoriasis) or young children, we’d recommend our blue smol non-bio capsules or our clear fragrance-free capsules which are also non-bio.

They still contain far fewer chemicals than the leading brands, are vegan and cruelty free, are delivered to your door, and they’re really gentle whilst still being super effective at cleaning your clothes. They are also dermatologically tested.

We have a great many customers with skin sensitivities such as eczema and psoriasis all happily using our non-bio and many of these customers have even reported improvements to their skin following the swap to smol. 

Luckily, at smol we offer free trials on both bio and non-bio laundry capsules so you can always try before you buy.