4.7 Loved by 35,000+ Guys

Gray Crew Neck Undershirt

From $42.00

Our gray crew neck is perfect for those who like their shirts fully buttoned up. Stay tucked and steer clear of sweat stains with a super-soft, breathable feel.

FABRIC FEATURES

  • Buttery Soft
  • Built to Last
  • Stay Cool & Fresh
  • No More Sweats Stains & Odors
  • Perfect Fit & Style
Size & Fit Guide

🎉

Over 96% of new customers keep theirs — because they love the fit.

1 shirt $42.00 per shirt
4 pack $35.50 per shirt
(Save $26.00)
6 pack $32.75 per shirt
(Save $55.50)
Best Value 10 pack $29.50 per shirt
(Save $125.00)

👉

Mix and match any undershirts to build your own multi-pack. Your discount applies automatically at checkout.

OUR 365-DAY COMFORT GUARANTEE

365 days. That’s how long you have to decide if UnderFit is your most comfortable undershirt. If it ever lets you down — collar, seams, or comfort — we’ll make it right.

SIZE & FIT
MATERIALS & CARE
TOP 5 BENEFITS

Confidence Starts
with the First Layer

Most undershirts are loose, bulky, and ride up throughout the day, trapping heat and adding unnecessary bulk. UnderFit solves these problems. Once you try it, you’ll never go back.

  • Stays Tucked – No adjusting needed.
  • Moisture-Wicking – Stay cool and dry.
  • Tailored Fit – No bulk under your shirt.
  • Ultra-Soft & Lightweight – All-day comfort.
BUILD MY PACK + SAVE UP TO 25%

The Most Comfortable Undershirt You’ll Ever Wear

The moment you put on an UnderFit undershirt, you’ll notice a huge difference compared to other undershirts you’re used to wearing. To design the best men’s undershirts, we analyzed everything we hated about traditional, poorly-made basics. That’s why we set out to make an undershirt that:

Build My Perfect Pack

  • Works for the office, a night out, or around the house.
  • Features the highest-quality, comfortable fabrics.
  • Stays tucked in all day long (with no “undershirt gut”).
  • Offers anti-odor and advanced moisture absorption.
Slim fit crew neck undershirt moves with you
Crew neck undershirt with gray quarter-zip sweater

A Perfect Fit That Keeps You Cool, Crisp, & Confident

You don’t need a six-pack to rock an UnderFit undershirt. They say clothes make the man. At UnderFit, we know confidence starts underneath.

Find My Fit

  • Look slimmer and feel more confident.
  • Stays tucked all day, no matter how you move.
  • Moisture wicking & odor resistant fabric keeps you feeling fresh.
  • Tailored fit hugs your biceps and waistline to eliminate lines and “t-shirt bulk” around your middle.

Ridiculously Soft & Sustainable

You’ll never want to take this undershirt off! Our undershirts are made from ProModal fabric, a highly-sustainable textile sourced from Beech Wood chips derived from the Birch Tree. The trees are sustainably farmed and our manufacturing process is “closed-loop,” meaning there is little to no waste.

Build My Perfect Pack

  • All-day breathability. Soft, light, and flexible.
  • Excellent durablility. No pilling after extended wear.
  • Wicks 50% more moisture than cotton.
  • 1/20th the environmental impact of cotton.
Crew neck undershirt with button down dress shirt

You’re A Reviews Person? We Got The Receipts

Menswear experts universally praise the Invisible Undershirt

Gotta tell you, it’s a very nice product. Good fit, good feel, good price. Comparatively, the UnderFit fits and feels very close (or as nice as) to the more expensive micromodal/lycra undershirts.

tug-review
Tug

Verified Buyer

No rising, No billowing. We managed to get through a whole day without a single untuck from under our made-to-measure shirts.

gents-review
The Gents Staff

Verified Buyer

The problem with most undershirts is that they’re just T-shirts. UnderFit’s shirts are made from lightweight yet durable fabrics with a touch of stretch and are designed to be worn under your shirts.

valet-review
Valet Staff

Verified Buyer

The Fit

The Best Fit or Your Money Back

Every UnderFit undershirt comes with a 365-day risk-free trial. If it’s not the best undershirt you’ve ever worn, we’ll make it right — no questions asked.

  • 35k+

    Guys Trust Underfit

  • 175k+

    Undershirts Sold

  • 100%

    Hassle-Free Returns

Frequently Asked Questions

If we haven’t answered your questions here, hit our chat or email us at service@woocommerce-736936-2725800.cloudwaysapps.com

TENCEL™ Fabric Feel

What makes it an invisible undershirt? Why is it beige?

Why do we use our TENCEL™ blend and not cotton?

Why do UnderFit undershirts cost more than cotton basics?

How do UnderFit undershirts stay tucked all day long?

What is the right fabric (moisture absorbing vs wicking) to wear?

What’s wrong with viscose, bamboo, organic cotton or other fabrics?

Where are the shirts made?

Finding The Right Fit

How does it fit?

Will it tighten to pull my belly in?

Will it feel tight?

Customer Service Questions

What if I try UnderFit and don’t like it?

What is your returns policy?

Do you ship worldwide?

Customer Reviews
4.8 Based on 674 Reviews
5 ★
84% 
565
4 ★
11% 
72
3 ★
4% 
24
2 ★
1% 
5
1 ★
0% 
8
Customer Photos
Write a Review Ask a Question

Thank you for submitting a review!

Your input is very much appreciated. Share it with your friends so they can enjoy it too!

Filter Reviews:
AL
03/05/2026
Adam L.
US US

Amazing

So far the very best undershirt ever!!

AK
03/03/2026
Adam K.
US US

Outstanding tee shirt

I love this tee shirt and the fit. The only issue I have is I wish I could wear it more confidently without a shirt over it as I live in South Fla. It’s a perfect shirt to wear alone but it shows the nipples and I’m unsure how to fix that issue. Otherwise it’s outstanding. I hope I can figure out a solution,

AK
03/03/2026
Adam K.
US US

Outstanding tee shirt

I love this tee shirt and the fit. The only issue I have is I wish I could wear it more confidently without a shirt over it as I live in South Fla. It’s a perfect shirt to wear alone but it shows the nipples and I’m unsure how to fix that issue. Otherwise it’s outstanding. I hope I can figure out a solution,

CF
03/03/2026
Craig F.
US US

Good shirts

First purchase from this company, the fit is good and they do what they're supposed to do.

DP
03/01/2026
Devon P.
US US

Great idea with unhelpful details

Color, cut, and fit are excellent and found nowhere else on the market. However, I wish the materials were a high mix of cotton or other natural materials. A combination of the material and the collar frequently creates irritation by the end of the day, even after several washes. I also suspect the synthetic materials will perform poorly in hot weather. I would buy 7 or 8 of these if it was only a cotton blend with a better collar.