Find Answers to Your Sweatnix Questions

Everything you need to know about Sweatnix undershirts, from sizing and care to performance and orders, all in one easy place.

Fit & Fabric

What makes Sweatnix different from regular undershirts?

Most undershirts are either synthetic and sweat-trapping, or natural but itchy — and almost none have a waterproof breathable underarm patch. Sweatnix solves all three problems with silver-infused Modal fabric and built-in pit protection that keeps you genuinely fresh, without deodorant.

Is the Sweatnix fabric suitable for sensitive skin?

Yes — our Modal fabric is naturally soft, breathable, and gentle against skin, making it ideal for those who find synthetic or rough fabrics irritating. It carries OEKO-TEX certification, meaning it's been independently tested and verified to be free from harmful substances.

How do I find my size?

We've made it easy — check out our comprehensive size chart on the product page for detailed measurements to find your perfect fit. The women's is quite a close fit, whereas the men's is a bit looser - so it's best to check your measurements against the chart.

Will the fabric feel clingy to my body?

Not at all — our Modal fabric is smooth and buttery against your skin, draping beautifully rather than clinging. It moves with your body for an effortlessly comfortable fit all day long.

Will the undershirt stretch or shrink over time?

We've machine washed ours many times and they still look like new — Modal is known for holding its shape beautifully. Just be sure to follow the care instructions on the label to keep yours looking their best.

Sweat & Performance

How does the sweat-proof technology work?

Our Modal fabric naturally wicks moisture away from your skin, while the breathable waterproof underarm patches create a complete barrier so sweat never reaches your outer clothing. Together, they work as a two-layer system that keeps you dry and confident all day.

Will it work under light-coloured or thin tops?

Yes — that's exactly what Sweatnix is designed for. The waterproof underarm patches mean no sweat marks ever break through, and the smooth Modal fabric gently streamlines your silhouette so it sits discreetly under even the lightest or most fitted tops without showing through.

Can I wear it during long work days or high pressure situations?

Sweatnix is designed for real life — long work days, big meetings, hot commutes, or any situation where sweat happens but isn't welcome. The moisture-wicking Modal and waterproof underarm patches keep you feeling fresh and confident from morning to night. Many of our customers also find them perfect for lighter workouts where comfort and freshness matter.

Does the fabric prevent odour?

Yes — silver-infused Modal is naturally antibacterial, meaning it actively inhibits the growth of odour-causing bacteria. It's one of the reasons many Sweatnix wearers find they no longer need deodorant at all.

Does Sweatnix help reduce visible sweat marks?

Yes — that's one of our superpowers. The waterproof underarm patches create a complete barrier between your body and your outer clothing, so sweat marks are a thing of the past, no matter what you're wearing. Just keep in mind your outer layer needs at least a short sleeve to cover the patch fully.

Orders & Exchanges

Do you offer free exchanges?

Yes — if your size isn't quite right, we'll happily exchange it for you. Simply return your item (Australian address) at your own cost and we'll cover the postage on your new one.

How do I request an exchange?

Simply email us to initiate your exchange and we'll guide you through the process. Once confirmed, post your item back to us at PO Box 53, Terrey Hills NSW 2084 and we'll get your new size on its way.

What is your refund policy?

We offer a 30-day refund guarantee, and you can return the undershirt even if you've worn and washed it — that's the whole point. Try it, wash it, see if it works. If you're not happy, return it within 30 days of receipt and we'll refund the product price. Customers pay return shipping unless the item is faulty. This guarantee is in addition to your rights under the Australian Consumer Law.

How long will my order take to arrive?

Australian orders typically arrive within 3-5 business days. For international orders, delivery times vary depending on your location — if you have any questions about shipping to your country, feel free to get in touch.

Can I change or cancel my order?

If you need to make a change or cancellation, email us as soon as possible and we'll do our best to help before your order is dispatched. Once it's on its way, we're unable to make changes — but our easy exchange and refund process has you covered.

Care & Wear

How should I wash my Sweatnix undershirt?

Easy care — machine wash cold and tumble dry on low. Treating them gently helps preserve the silver-infused fabric and waterproof patches so they keep performing wash after wash.

Can I wear it multiple days in a row?

Thanks to the antibacterial silver-infused Modal, Sweatnix stays fresher for longer than a regular undershirt — so most wearers do get more than one wear between washes. We've had at least 3 over winter under our knits! That said, we'll leave that call to you and your nose!

Is it safe to use fabric softener?

No. We recommend skipping the fabric softener — it coats fibres with a silicone-based layer that blocks the silver's antibacterial effectiveness and reduces Modal's natural absorbency and breathability. A mild liquid detergent on a cold wash is all you need to keep your Sweatnix performing at its best.

Does the fabric wrinkle easily?

Modal can crease a little, but because Sweatnix is designed to fit snugly against your skin, any wrinkles smooth out naturally once you put it on. You'll never notice them under your outfit!

Is the fabric quick drying?

Yes — Modal is naturally quick drying. We like to line dry first and finish in the dryer on low if needed, which keeps them in great shape and ready to wear again in no time.

Still Have Questions?

We’re here to help you feel confident and supported at every step of your Sweatnix experience. Whether you need help with sizing, orders, or product information, our team is ready to assist you.

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