image of pink bar soap that says "smooth skin, smooth sailing"

Should you put a bar of soap under your sheets?

Plus more strange uses for bar soap

Last Updated: January 25, 2022

Guess what! Bar soap is good for more than washing your skin. We’re coming clean about the wonderful, surprising, and sometimes mythical ways bar soap can improve your life.

Bar soap really gets around. The first use of soap dates back to 2800 BC, when ancient Babylonians crafted a soap-like material made from animal fat and ashes to wash wool.

These days, bar soap is used for much more than just washing. It’s a total workhorse. From your bed to the backyard, it’s got more uses than you can imagine.

We’re coming clean in this article about the wonderful, surprising, and sometimes mythical ways bar soap can improve your life.

How to use bar soap in your bed

Yes, you read that right. Outside of the normal uses for bar soap (to wash your body, hands, or face in the shower), you can try out bar soap in your bed.

Here’s how:

Bar soap under mattress for bed bugs

A bar of soap under your mattress could help deter bed bugs from infiltrating your abode. But, not just any old bar soap will do!

Bed bugs aren’t huge fans of cedar or peppermint scents. A bar of Grove Co.’s Hydrating Bar Soap in cedar + sage or peppermint will do the trick. Snag a few of these and put them near the floorboards by your bed or tuck ‘em inside your bed frame to keep bed bugs at bay.

Bar soap for restless leg syndrome

Restless leg syndrome, or RLS, is a neurological disorder that causes leg cramps when a person tries to relax at night.

While there’s no scientific evidence to back it up, some people say that adding a bar of soap under your sheets helps soothe their RLS-related cramps. Grove Co.’s Lavender soap is a good choice, as the soothing scent of lavender has a calming effect that’ll help you relax and drift off to sleep.

If you suffer from RLS and placing a bar of soap under your sheets isn’t your cuppa tea, try this on for size. Some research shows that RLS could be related to a magnesium deficiency, and magnesium supplements have been shown to help with insomnia caused by RLS in some cases.

Read up on magnesium supplements and learn how to incorporate them into your routine for deeper relaxation.

Grove Tip

Did you know you can make liquid soap from bar soap?

If you’ve ever fancied yourself as an eco-friendly alchemist, this hack is for you.

Take a new bar of soap (or those leftover soap nubs you’ve been saving) and grate them—you’ll need at least 4 ounces.

Put the soap shreds in a saucepan with 8 cups of water and heat until the soap melts. Remove the mixture and let it cool overnight.

The next day, blend the thickened soap with a whisk or beaters then store it in upcycled soap containers or reusable soap glass dispensers.

How to use bar soap in the great outdoors

sun illustration

Here are some quick tips to keep clean when you’re spending time around some natural dirt outside.

Bar soap to keep under your nails clean

Love gardening? Us, too.

Before you dig in the dirt though, try digging your nails into a bar of soap. The soap stops soil from getting under your nails and it rinses off like a charm after you’re done in the yard.

Bar soap to clean your cast iron

Cooking over a campfire is the bee’s knees, but cleaning up is a bit of a pain.

Next time you take a trip to the great outdoors, rub a wet bar of soap on the bottom of your cast iron pan. It’ll help grab the soot and make it easier to wash off post-grub.

While you’re at it, find more sustainable camping supplies for your next trip and learn how to properly clean that dingy tent from last season too.

How to use bar soap in your hair and makeup routine

Bar soap, outside of washing your face, is actually kind of useful for your hair and makeup routine. Have a look.

Soap brows

Soap brows are the latest beauty trend to take over Instagram and TikTok.

What you need: A soap that contains glycerin, like Yes To Coconut Ultra Hydrating Milk Bar Soap.

What you’ll get: Bushy brows worthy of Cara Delevigne.

Get your soap damp, but not wet, and run a clean spoolie (aka mascara wand) over it. Brush the spoolie through your brows in an up-and-out motion. After the soap dries, it’ll hold your brows in place for gorgeous, full brows. Got sparse spots? Take a brow pencil and fill ‘em in.

Confused? Watch it in action here:

Hair shampoo and conditioner soap bars

Bar soap isn’t just for your body anymore.

Peach not Plastic, an innovative brand dedicated to making bathtime fun and sustainable, has a zero-waste line of shampoo and conditioner bars that cleanse and soften hair using all-natural, cruelty-free ingredients.

Check out our Peach shampoo and conditioner bar review from an actual Grove writer who tried it out and see how they held up to conventional hair products.

How to use bar soap with your clothes

Yes, bars of soap can even help you clean and protect your clothing. Here’s how …

Bar soap to banish moths

Keep moths away with a handy dandy bar of soap. Cedar is a classic choice to banish moths from your wool, but not everyone wants their favorite sweater to smell like a forest.

Lavender scents, like Mrs. Meyer’s Lavender Bar Soap, are also effective.

Got moths in your pantry? We have a remedy for that, too.

Bar soap to freshen up drawers and closets

Putting bar soap in your drawers and closets is a great way to make your clothes and linens smell fresh.

Drop a whole bar into each of your drawers, chop it into quarters, or use a cheese grater to shred the soap and put it in sachets that hang in your closet.

Need a yummy-smelling rec? Try Pacha Soap Co.’s Pacha Peaces—it comes with seven hand-crafted soaps that smell totally divine.

Bar soap to unstick a zipper

Drag a dry bar of soap over your zipper teeth to help a stuck zipper glide with ease.

This is an excellent hack for vintage clothes with sticky zippers, too!

How to use bar soap for sewing

We’ve got two quick tips for using a bar of soap while you’re sewing.

Bar soap to mark fabric

If you ran out of tailor’s chalk in the middle of a project, fear not. Head to the bathroom for your trusty bar soap and use it to mark seams and hemlines on your fabric.

Just make sure the soap is dry!

Bar soap to coat needles

Some fabrics are notoriously tricky to sew, but we’ve got a hack: Stick your sewing needles in a bar of soap.

Sure, it sounds kind of weird, but the thin layer of soap helps your needles glide through fabric more easily.

Grove Tip

How do you make felted soap?

Felted soaps create a luscious lather, gently exfoliate your skin, and make a great gift.

Grab some wool roving and any bar soap (may we suggest this charcoal and Brazilian clay bar by Terra Beauty Bars?) and wrap the bar in the roving until the soap is completely covered.

Stick the felted soap in a nylon stocking and run hot water over it, massaging the soap so the wool adheres to it.

Once the wool is attached to the soap, pull the bar out. Felted soap!

A few more FAQs about bar soap

What can I do with unused bars of soap?

All of the soap hacks listed above are great for unused or leftover soap.

Alternatively, you can put your unused bits of soap in a soap saver bag. These cotton bags create a fantastic lather, exfoliate your skin, and help you use up every last bit of your bar soap.

Can you bring a bar of soap on a plane?

Yes! Bar soap is ideal for air travel because it’s considered a solid.

If you’re concerned about the space a bar of soap will take up, consider cutting the bar into quarters and only take one or two of the chunks with you.

Remember to store your soap in a bar soap travel case or a silicone bag.

Does bar soap expire?

Conventional bar soaps expire after two to three years, while natural soaps expire after one to two years.

If your soap lathers and smells good, it’s still effective.

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