Soap vs. Detergent: What Is the Difference?

Soaps and detergents are cleaning agents that help remove dirt, bacteria, and other unwanted particles from human skin, textiles, and other solid surfaces. People often use the words “soap” and “detergent” interchangeably since both of these products serve cleaning purposes. Moreover, many detergents are marketed as soaps to appear more natural nowadays.

But in fact, there are significant differences between these two types of cleaners. If we compare soap vs. detergent, we’ll notice that these substances differ in composition, structure, uses, and properties.

Quick answer: The main difference between soap and detergent is how they’re made. Soap is made when oils or fats react with lye to form alkali salts of fatty acids. Detergent is made with synthetic surfactants, often from petroleum-based ingredients. A non-detergent soap is true soap that cleans without synthetic detergent ingredients.

Soap vs. Detergent: Key Differences

What is Non-detergent Soap?

A non-detergent soap is a true soap made mainly from alkali salts of fatty acids and contains no synthetic detergents.

The truth is there are very few true all-natural soaps on the market. Most commercially manufactured liquid and solid body cleansers are synthetic detergent products. And although some of these detergent products are marketed as “soap” by their manufacturers, they are not true soap according to the regulatory definition made by the FDA.

So what is non-detergent soap? According to the FDA, the product can be defined and regulated as soap only if it meets the following conditions:

• It must be made mainly of the “alkali salts of fatty acids,” which is what you get when you combine animal fats or vegetable oils with lye.
• The “alkali salts of fatty acids” must be the only ingredients that cause the product’s cleaning action. If the product contains synthetic detergents, it’s considered a cosmetic. Still, manufacturers can use the word “soap” on the label.
• The product must be labeled and marketed only to be used as soap. If it’s intended to moisturize the skin, deodorize the body, or make the skin smell nice, it’s a cosmetic. And if the product is intended to kill germs to prevent disease or treat a skin condition, such as eczema or acne, it’s a drug. But manufacturers can use the word “soap” on the label.

Products that meet these criteria are regulated by the Consumer Product Safety Commission (CPSC). And if a cleanser does not meet all of these criteria, it’s either a cosmetic or a drug and is regulated by the FDA.

At Botanie Soap, we make products that meet all criteria of the regulatory definition of soap. We only use the cold-process method that allows us to have complete control over the ingredients and offers many possibilities to create customized bar soap and liquid soap. We can develop custom soap solutions for your brand if you are looking for custom production.

How Soap and Detergent Are Made

Although soaps and detergents are both surfactants, they are not the same. A surfactant is a washing compound that helps grease and water mix so dirt and oil can be removed. The major difference between soap and detergent is that soap is produced from natural ingredients such as vegetable oils and animal fats. In contrast, detergent is made from synthetic sources, including petroleum fractions. As a result, soap is biodegradable and less harmful to the environment than regular, mainstream detergents.

Traditional soaps are made by mixing fats or oils and an alkali, such as lye. The lye reacts with the oils and turns the mixture that starts as a liquid into blocks of soap. This reaction is known as saponification. However, commercially produced soaps may contain added chemicals for particular colors and fragrances.

At Botanie Soap, we never add chemicals and use only natural ingredients to produce soap bars and liquid soaps that we offer for private-label use. That’s why our products are great for skin care and friendly to the environment. For example, our Oatmeal Spice Bar Soap is made from saponified organic sunflower, coconut, palm, and safflower oils, oats, and essential oils of clove bud and cassia.

Bulk Liquid Soap

Bar Soap - 4 oz

Bar Soap - Hotel Size

Samples

A Short History of Soap and Detergent

Soap has been used for thousands of years, but modern bar soap became widely available in the 19th century as manufacturing improved and public hygiene became more important. Castile soap, made from olive oil, was produced in Europe as early as the 16th century. Synthetic detergents became more common in the 20th century, especially after World War I, when animal fats were in short supply. By the 1950s, detergents had become common in homes because they worked well for laundry, dishes, and heavy-duty cleaning.

Detergents contain synthetic ingredients—manmade sulfates, usually derived from petrochemicals, which clean hands, hair, clothes, and dishes when they come in contact with water. Detergents can include many other ingredients to suit specific cleaning tasks, such as fillers, abrasives, optical brighteners, enzymes, colors, artificial fragrances, etc. Because of this versatility, detergents can be used in everything from shampoo to multi-purpose cleaners to hand cleansers and stain removers.

What This Means for Soap Brands

For brands, the difference between soap and detergent affects more than ingredients. It can affect product claims, labeling, customer expectations, and brand positioning. If your customers care about clean ingredients, natural sourcing, and a traditional soapmaking process, true soap may support that message better than a detergent-based cleanser.

Botanie makes cold-process bar soap and liquid soap for brands that want natural formulations, private-label options, and repeatable production at scale. If you are looking for custom production, our custom all-natural soap manufacturing process can help you build a scalable soap line without managing formulation, production, and batching yourself.

Detergent-Free Soap: What Are the Advantages?

Detergent-free soap made using the traditional cold-process method, which we use at Botanie Soap, is eco-friendly. It is produced with natural products (plant oil base, lye, and essential oils) and requires less energy during manufacturing.

These detergent-free soaps have a pH of 8 to 10 (alkaline), which makes them effective cleansing agents and eliminates the need for harmful antibacterial chemicals and preservatives. At the same time, traditional all-natural soaps don’t cause allergies and are gentle on the skin as they retain all the natural glycerin.