If you’re a fan of traditional bar soap, you’ve likely asked this question at some point: “What bar soap lasts the longest?” Not all soaps are created equal, and some brands are notoriously fast-melting compared to others.
In this article, we take an in-depth look at some of the longest-lasting bar soap brands on the market. We will also provide tips on how you can make your bar soap last longer.
What Makes a Soap Bar Last Longer Than Others?
Here’s the deal:
To make a bar of soap last longer, it either has to be less soluble in water or contain less moisture initially. Technically speaking, it’s about the balance of fats and alkalis in the soap. Also, triple-milled soaps tend to last longer than others because of their compactness and lower moisture content.
So you can either get a very large soap bar that is not so soluble in water or a small, triple-milled soap bar.
Types of Soaps & Their Longetivity

When shopping for bar soap you’ll come across three predominant types: traditional, artisanal, and syndet (synthetic detergent) bars.
Traditional soaps are crafted using old-fashioned soapmaking techniques. They use animal fats or vegetable oils and are great for your skin’s natural pH. While traditional soaps can last reasonably long, their moisture content can lead them to dissolve more rapidly than other kinds.
Artisanal soaps are homemade or small-batch soaps made by soapmakers. These soaps often use unique blends of oils, butters, and additives that can affect the bar’s hardness and longevity. For instance, a coconut oil soap will last longer than a soap mainly composed of softer oils like olive oil.
Syndet bars, aren’t technically soap but are made using synthetic surfactants. They are often more pH-balanced and gentler on the skin than traditional soap, and because of their composition, they tend to last longer than other types.
Milling Process
As previously mentioned, the milling process greatly affects how long a bar soap lasts. The process involves grating the soap, then compressing it back together. This is done multiple times, leading to a dense, long-lasting bar.
Triple-milled soaps or French-milled soaps have been passed through the milling process three times, creating a very dense and long-lasting bar. This process also creates a smooth, luxurious lather. In addition to lasting longer, these soaps are more expensive due to the added labor and time.
Here’s a fascinating video outlining the process:
Regular or non-milled soaps, on the other hand, go through a less intensive process, keeping the moisture content higher and their lifespan shorter.
Where Do Castile Soaps Fit In?
Castile soaps are a type of traditional soap that originated in the Castile region of Spain. They’re unique because they’re made with 100% olive oil, as opposed to a blend of different oils. This results in a very mild soap that’s great for those with sensitive skin. On the downside, pure olive oil soaps tend to be softer and have a lower lather, which means that they may not last as long as soaps made with harder oils or those that have gone through the milling process.
However, many soapmakers today create “bastille” soaps, a spinoff of Castile soaps that include a small percentage of other oils to increase hardness and lather while maintaining Castile soap’s gentle nature. These tend to last longer than pure Castile soaps.
How To Extend the Life of Your Soap Bar
While the brand of soap you choose plays a significant role in the soap’s longevity, your handling of the soap will have a significant impact as well. Here are some tips for extending the life of your soap bar:
- Allow it to Dry Out: After using your soap, don’t let it sit in water. Instead, place it on a soap dish with proper drainage to ensure it dries out completely.
- Store in a Cool, Dry Place: Humidity is not a friend to your soap. Make sure you store your soap in a cool, dry place away from direct sunlight.
- Use a Washcloth: Instead of applying the bar directly to your skin, use a washcloth or a loofah. This way, you’re utilizing less soap but still getting enough lather.
We discuss these and more soap-saving strategies at length in our separate article, on how to properly store your soap.
Bar Soap Brands That’ll Last Longer Than Others
Here are a few bar soaps that you should consider if you want one to last you for weeks, not days:
1. Duke Cannon Big Ass Brick of Soap

Aptly named the Big Ass Brick of Soap, Duke Cannon’s offering is 3x the size of your regular bar soap and is known for its long-lasting qualities. To boot, it is triple-milled and made with premium ingredients that provide a robust lather. It does not contain harsh cleansers and is available in a variety of appealing, masculine scents.
2. Sterling Soap Co. Bath Soap

While Sterling is most often associated with their high-quality shaving soaps, their bath soaps are also a fantastic, long-lasting option. With 85 different scents to choose from, they are bound to have a fragrance you’ll love.
The soaps are made with a mixture of tallow, coconut oil, shea butter, and a plethora of other skin-loving ingredients. These materials increase the hardness of the soap and contribute to its longevity. Additionally, they’re handcrafted and cured for six weeks, a process that further extends the soap’s lifespan.
3. Pre de Provence Artisanal Soap

Known across the globe for the quality of their soaps, French brand Pre de Provence creates luxurious, long-lasting bars. Rather than being triple-milled, Pre de Provence soaps are quadruple-milled, resulting in a denser, harder, and incredibly long-lasting bar. The high concentration of shea butter in their soaps keeps your skin moisturized and soft while ensuring a prolonged lifespan for the soap itself.
Despite the French heritage and intense milling process, the soap is surprisingly affordable. It is free from parabens, sulfates, and phthalates and is available in numerous floral, woodsy, and clean scents that transport you straight to the French countryside.