Home/Scarlet Period | Made for a Light Flow/Underwear Starter Set
Scarlet Period Underwear Starter Kit
Scarlet Starter Kit comes with two pairs of period underwear.
Scarlet PFAS-Free Period Bikini Brief – Stylish, Leak-Proof, Organic Cotton
Scarlet PFAS-Free Period Bikini Brief – Stylish, Leak-Proof, Organic Cotton
Scarlet PFAS-Free Period Bikini Brief – Stylish, Leak-Proof, Organic Cotton
Scarlet PFAS-Free Period Bikini Brief – Stylish, Leak-Proof, Organic Cotton
Scarlet Period All Over Cleanser is naturally scented with an allergen-free and pH-friendly
Scarlet Period Underwear Laundry Bag | Lightweight mesh delicates washing bag
Scarlet Period Underwear Starter Kit
Scarlet Starter Kit comes with two pairs of period underwear.
Scarlet PFAS-Free Period Bikini Brief – Stylish, Leak-Proof, Organic Cotton
Scarlet PFAS-Free Period Bikini Brief – Stylish, Leak-Proof, Organic Cotton
Scarlet PFAS-Free Period Bikini Brief – Stylish, Leak-Proof, Organic Cotton
Scarlet PFAS-Free Period Bikini Brief – Stylish, Leak-Proof, Organic Cotton
Scarlet Period All Over Cleanser is naturally scented with an allergen-free and pH-friendly
Scarlet Period Underwear Laundry Bag | Lightweight mesh delicates washing bag

Underwear Starter Set

Making the switch, made simple.

$62.00 $72.00

New to reusable period care? Start here. Bikini Briefs, the pH-balanced cleanser and a mesh laundry bag. You'll wonder why you didn't sooner.

    Organic Cotton Softness
    PFAS-Free & Toxin-Free
    Machine Washable
    Stylish and ultra-flattering fit
Scarlet Period Bikini Brief (Light or Moderate) (Size)
Scarlet Period Bikini Brief (Light or Moderate) (Style)

If you’re going to make the change to eco-friendly period underwear, you might as well do it right. From our best-selling PFAS-free, organic cotton bikini briefs (available in light or moderate absorbency) to our all-natural, pH-balanced All-Over Daily Cleanser, you’ll wonder why it took you so long.

Also included is one of our handy Laundry Bags, so wash day can suck a little less.

✨ Rinse in Cold Water: After wearing, rinse in cold water until it runs clear to keep them fresh.

✨ Machine Wash Cold: Toss them in with mild detergent (no bleach or fabric softener, please).

✨ Dry with Ease: Line dry or tumble on low - no need for extra care.

✨ Need more info? Please read our complete guide to caring for your period underwear here.

✨ Bikini Briefs: Crafted from 95% GOTS-certified organic cotton with a PFAS-free, quick-dry gusset - breathable, soft, and built for leak-proof protection.

✨All-Over Daily Cleanser: A gentle, pH-balanced body wash designed for sensitive skin (including your vulva). Infused with calendula, hemp seed extract, and jojoba oil to calm, hydrate, and support skin health.

✨ Fit Note: Our underwear runs on the slightly smaller side - if you're between sizes, size up.

✨ Teen-to-Adult Fit: Our sizing is unique - please refer to both the numerical (e.g. 10, 12) and letter sizing (e.g. M, L) in our guide.

✨ Australian Sizing: We use AU sizes - international customers, check our Size Guide.

✨ Still Unsure? Contact us for advice. We love a chat!

Did you know that over 12 billion pads and 7 billion tampons end up in landfills yearly? By choosing Scarlet, you're supporting a more sustainable future - where self-care and sustainability go hand in hand.

✨ High-Quality, Safe Fabrics: Made with care, free from PFAS and harmful chemicals, and independently lab-tested for your safety.

✨ Eco-Conscious Manufacturing: Crafted with a focus on quality and reducing environmental impact.

✨ Recyclable Packaging: Minimal waste for a cleaner world.

✨ 1% for the Planet: Scarlet is proud to contribute to environmental stewardship with every purchase.

Size Chart

Size chart for Underwear Starter Set
Scarlet Period Underwear Starter Kit

Underwear Starter Set

$62.00 $72.00
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SCARLET BIKINI IS PERIOD PROOF

Everyday Period Undies That Feel Like, Well, Normal Undies

Today's schedule: gym, work, drinks, dinner, date. There's no time for stains and leaks.

Our Bikini Brief offers hours of leak-proof protection. Made with breathable and buttery soft organic cotton, it's period underwear that feels like you're wearing, well, regular underwear.

  • Super soft GOTS Certified Organic Cotton
  • Chemical treatment-free, including PFAS
  • Available in two absorbencies
BUY NOW

Your Questions, Answered

How do they work?

Scarlet Period Underwear is designed to fit like normal underwear and features multi-layered leak-proof technology that wicks away moisture, absorbs fluid, and contains it to keep you dry and protected. 

The built-in leak-proof technology is harder working than disposable pads which means it can safely hold more liquid and last for years not hours. Loved by all; you can read some reviews.

Do I need to wear a cup, tampon, or pad too?

Depending on the absorbency you choose and the heaviness of your flow, you can wear our period undies on their own or as backup along with a Period Cup or tampon.

What does the absorbency level mean?

Super Light: Holds up to 1 teaspoon, equal to less than one regular tampon. Think of it as a new-age panty liner, great for spotting, light leaks and discharge. Try: Invisible Thong

Light: Holds up to 3 teaspoons, equal to 2 regular tampons or one pad. For light days, drips and discharge. Try: G-String or Bikini Brief in Light-Moderate

Moderate: Holds up to 5 teaspoons, equal to 3 regular tampons or 2 pads. For moderate days, or as extra defence on heavy days with our Period Cup. Try: High-Waist Brief or Bikini Brief in Moderate-Heavy

Heavy: Holds up to 7 teaspoons, equal to 4 regular tampons or 3 pads. Our heavy hitters are great worn on their own, day or night. Try: Boyshort or Period Cup

How do I wash them?

After use, rinse them in cold water (we recommend in the shower) until they run clear. Then, machine wash in cold water with mild detergent (no bleach!). Try our Laundry Bag to safeguard them on laundry day. Then just hang out to dry (the sunnier the better) or tumble dry on low - that’s it!

TIP: If it’s your first wear, pop them in the washing machine with your next cold cycle - washing them before wearing activates their absorbency even more.

What is your 30-day risk-free trial?

We offer a 30-Day Risk-Free Trial for first-time shoppers for one pair of underwear. If you’re unsatisfied or have sizing concerns, email us at support@scarletperiod.com.

How do I pick the right size for me?

We get it, sizing for bottoms is anything but standardised. Which is why this size guide will help break it down for you. Make sure to check both our numeric and letter sizing so no confusion (ie. our large is a 12).

When in doubt, feedback tells us better to size up. Still confused? You can also email us for help at support@scarletperiod.com.
★★★★★

"This Aussie-based label is putting the cool into period knickers."

Refinery29

★★★★★

'Scarlet is all about cruelty-free, paraben-free, and 100 per cent period care alternatives that are gentle on the environment."

Harper's Bazaar

★★★★★

"Australian start-up Scarlet is the Glossier of period products."

Fashion Journal

Real advice for real cycle days