How to make bar soap last longer: storage, soap dishes and good habits

A natural soap bar is softer than the hard white blocks many of us grew up with. That softness is the point: it is what makes the lather creamy and the wash gentle. It also means the bar needs a little care. Treated well, a handmade bar lasts for weeks. Left in a puddle, the same bar can be gone in days.

The good news is that almost all of the difference comes down to one thing, and it is easy to get right.

Why handmade bars are softer

Traditional soap keeps the glycerin that forms naturally when oils are turned into soap. Glycerin attracts water, which is kind to your skin and less kind to a bar sitting in a wet dish, because it draws moisture into the soap. Handmade bars are also usually made with a little extra oil left unreacted, and contain none of the hardening agents used in mass production.

In short: the qualities that make the bar pleasant to use are the same ones that make it vulnerable to standing water. The answer is not a harder soap. It is a drier bar.

The one rule: let it dry

Soap wears away in two ways. A little is used each time you lather. A great deal more is lost if the bar stays wet between uses, because the surface softens into a gel that washes straight down the drain the next time you pick it up. Keep the bar dry between uses and you remove the second kind of loss entirely.

Everything else in this article is a way of following that one rule.

Choose the right dish

If you buy only one thing to go with your soap, make it a dish that drains.

Put it in the right place

Position matters as much as the dish. In the shower, keep the bar out of the direct spray and away from where water runs down the wall. A high shelf or a corner on the far side from the shower head is ideal. At the basin, keep it where splashes do not reach it.

Air flow helps. A bathroom with an open window or an extractor fan dries a bar far faster than a closed, steamy one. If your bathroom stays damp for hours, consider keeping the bar just outside the shower enclosure.

Lather in your hands, not on your body

Turn the bar a few times between wet palms, set it down, and wash with the lather. Rubbing the bar directly over your skin, and especially over a rough cloth or sponge, uses several times more soap than you need. A wash cloth or a natural sponge is fine, and gives a richer foam, but load it with lather from your hands or with two or three light strokes, not twenty.

Use warm rather than very hot water. Hot water softens the bar faster.

Rotate two bars

If a bar is used several times a day it never has the chance to dry. Keeping two on the go and alternating them gives each a full day to harden. Both will last longer than they would have alone. Many households keep one at the basin and one in the shower for this reason.

Cut a large bar in half

A large bar has a large wet surface. Cutting it in two with a sharp kitchen knife and using one half at a time means half the soap stays perfectly dry until you need it. The smaller piece is also easier to hold.

Store spare bars properly

• Keep them somewhere cool, dry and out of direct sunlight. A linen cupboard or a drawer is perfect; a steamy bathroom shelf is not.
• Leave them in their paper wrapping or wrap them in cloth. Soap should breathe. Avoid sealing bars in plastic.
• Soap continues to harden as it ages, so a bar stored for a few months usually lasts longer in use.
• Natural scents fade with time and light. For the best fragrance, use bars within about a year.
• A spare bar in a drawer scents your linen while it waits.

Use the last sliver

When a bar becomes too thin to hold, do not throw it away. Wet it and the new bar, press the sliver firmly on top, and leave them to dry overnight; by morning they will have become one. Alternatively, collect slivers in a soap saver bag and use the bag itself as a lathering pouch.

Soft water, hard water

In hard water, soap lathers less, and it is tempting to keep rubbing. Use a cloth to build the foam instead. In very soft water, soap lathers easily and can take longer to rinse, so use a little less. Neither changes how the bar should be stored.

When travelling

Let the bar dry before you pack it. Carry it in a tin with a little air, a ventilated case, or a wrap of waxed cloth, and take it out to dry when you arrive. A bar sealed wet in an airtight box for a week will turn soft, though it will recover once it has dried out.

How long should a bar last?

It depends on the size of the bar, the oils it is made from, how many people use it and how often. As a rough guide, a standard bar used by one person once a day and kept dry between uses lasts around four to six weeks. If yours disappears much faster than that, the dish is almost always the reason.

Why does my bar soap run out so fast?

• It sits in water between uses, so the surface dissolves and washes away.
• It is in the direct spray of the shower.
• It is rubbed directly over skin, a cloth or a sponge rather than lathered in the hands.
• The water is very hot.
• Several people use the same bar many times a day, so it never dries.
• It is a soft, young or very high-glycerin bar that has not been fully cured.

How to store bar soap without a soap dish

• Stand the bar on its edge on a dry shelf so only a thin side touches the surface.
• Put it on a bottle cap, a small wooden block or a folded natural loofah to lift it off the surface.
• Use a soap saver bag and hang it from the shower fixture.
• Keep it on the window sill or a shelf outside the shower and bring it in when you wash.

Making a bar smell nice for longer

Natural scents fade with time, air and light. Keep spare bars wrapped and in a cool, dark drawer, and only unwrap a new one when you need it. The bar in use loses its scent faster if it stays wet, so drying it between uses helps the fragrance as well as the bar.

Can you turn bar soap into liquid soap?

Yes, and it is a good way to use up slivers or a bar you do not enjoy on its own. Grate the soap finely, then stir it into hot water until it dissolves. As a rough starting point, use about a tablespoon of grated soap for each cup of water, and adjust: more soap gives a thicker liquid. Let it cool and thicken for several hours, then whisk or blend it smooth before pouring it into a pump bottle.

A few honest caveats. Homemade liquid soap is thinner and less stable than commercial products; it may separate, thicken unevenly or turn cloudy, and a shake usually fixes it. Because it contains a lot of water and no preservative, make small batches, keep it out of direct sunlight, and use it within a few weeks. Use boiled or distilled water to reduce the risk of anything growing in it. If it develops an odour or mould, throw it away.

It also changes the economics. A bar dissolved in water does not clean any more surfaces than the bar would have done; you are trading a solid for a convenient liquid. For hand washing by the sink, many people find that convenience worth it, especially for slivers that would otherwise be wasted.

If you would rather keep the bar a bar, the soap saver bag remains the simplest way to use every last piece: drop slivers in, wet the bag, and lather straight from it.

The answer is not a harder soap. It is a drier bar.