Woman in yellow and white outfit sitting on a beige background with promotional text overlay.Woman sitting on a white background with promotional text overlay for a sale event.
Woman in yellow and white outfit sitting on a beige background with promotional text overlay. Woman sitting on a white background with promotional text overlay for a sale event.

Sweat Proof. Guaranteed.

Hot days, long weekends, and outfits worth repeating. This 4th of July, we’re giving you 20% off everything*

Apply code SUMMER25 at checkout.

*Excludes Last Chance items

Shop All Sweat-Proof Undershirts
Back In Stock
#color_almond #color_almond
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The Signature Undershirt $65.00
4.68 reviews
#color_white #color_white
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The Crop Undershirt $65.00
4.7 reviews
#color_taupe #color_black
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The Merino Wool Short-Sleeve Crewneck Undershirt $85.00
5.0 reviews
#color_black #color_almond
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The Lace Undershirt $65.00
4.76 reviews
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#color_almond #color_white
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The Square Neck Cap Sleeve Undershirt $65.00
4.37 reviews
#color_almond #color_truffle
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The Semi-Fitted Undershirt $65.00
4.74 reviews
Sold out
Back In Stock
#color_black #color_black
XS
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The Merino Wool Signature Undershirt $85.00
4.7 reviews
Back In Stock
#color_grey #color_white
XS
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The Short-Sleeve Crewneck Undershirt $65.00
4.8 reviews
New Arrivals
#color_black #color_black
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The Short Sleeve Lace Overlay $75.00
5.0 reviews
#color_almond #color_white
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+1
The Three Quarter Undershirt $65.00
4.72 reviews
#color_black #color_black
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The Merino Wool Long-Sleeve Crewneck Undershirt $100.00
4.64 reviews
New Arrivals
#color_black #color_black
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The Boatneck Undershirt $65.00

fresh all day

Sweat-Proof Undershirts

Keep your clothes clean and fresh with our sweat-proof undershirts. Built-in underarm shields provide unmatched moisture-wicking and sweat protection, ensuring you stay comfortable and your outerwear stays spotless throughout the day.

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embrace the natural

Merino Wool

Naturally thermoregulating, odor-resistant, and perfect for layering, it’s the ultimate base layer for the chilly months ahead.

Shop merino wool

Finally, an undershirt that covers my bra and doesn't squeeze the breath out of me. The semi-fitted undershirt is a great fit for me, and it doesn't show under fitted sweaters!

Valerie Sinclair

Once you’ve tried these undershirts, you can’t live without them. They regulate your temperature, wick your sweat, hide your bra under transparent blouses, and reduce the need for washing and ironing your shirts and blouses!! I love everything about them and similar brands just don’t match this quality.

Grace Morrish

I love this shirt. It even works nicely as a main shirt under a cardigan sweater or jacket. It’s thin enough that it doesn’t show under blouses, dresses, or other clothing I want to protect. I love it.

Heather Cogdell
#color_truffle The Semi-Fitted Undershirt
#color_almond The Signature Undershirt
#color_almond The Lace Undershirt

FAQs

Frequently Asked Questions

What makes Numi’s sweat-proof undershirts different from regular undershirts?

Our sweat-proof undershirts feature built-in underarm shields that wick away moisture and prevent sweat from reaching your outerwear. This keeps your clothes clean and fresh all day.
Are the sweat-proof undershirts comfortable to wear all day?

Yes, our undershirts are designed with comfort in mind. They’re made from a soft, stretchy fabric that feels great against your skin and moves with you throughout the day.

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