The 7 best men's undershirts to keep your outfits sweat-free, comfortable, and sharp

We nearly gave up on T-shirt style undershirts. They can be ill-fitting at the collar, the sleeves can become loose over time, and they rarely stay tucked in. But Tommy John's undershirts solved all of our gripes. Close-fitting but not tight, they're long enough to stay comfortably tucked into your pants, and they practically disappear underneath your top layer of clothes. 

We especially like Tommy John's undershirts when wearing dress shirts. They're more comfortable (which is important when you're already wearing not-so-comfortable dress clothes), they help prevent sweat stains on the armpits, and they're a lot less visible if you're wearing a white or light-colored shirt because they lay flat.

Read our full review of Tommy John undergarments.

V-neck undershirts serve a purpose other than style: When sporting a button-up shirt, you can leave the top button undone while still hiding the shirt underneath. And if you're going for a super casual look with two or three buttons undone, you'll need an even deeper V-neck. 

All Citizens' AirWeight Undershirt is a solid choice because it offers the option of a standard V-neck or a deep V-neck. The shirt also features mesh zones on the sides for breathability, a stay-tucked length, and a soft microfiber feel on the skin.

While T-shirt style undershirts are best for preventing armpit stains under button-ups and dress shirts, tank top undershirts get the job done if you're only concerned with having a sweaty back and chest. The Hanes Cool Comfort White Tank is a no-frills undershirt, but with no tags, soft preshrunk cotton, and moisture-wicking technology, it has everything you need.

In line with all of Hanes' other products, the Cool Comfort tank tops are reasonably priced within everyone's budget. Although we regularly recommend skipping low-cost underwear for pricier, more durable options, we have found no issues with Hanes tank tops that should deter you from buying them.

What would a list of undershirts be without Hanes? In short, incomplete. As one of the most popular underwear brands, if not the most popular, Hanes has a huge assortment of all types of undergarments, including undershirts. If you're going for a classic T-shirt style rather than a tank top, the Ultimate Comfort Crewneck is what you'll want to buy, especially if you're on a budget. 

Each pack comes with four undershirts, making it the best bang for your buck. Made from 95% cotton and 5% Spandex, these Hanes undershirts are tagless, have lay-flat collars, and are available in sizes up to 2XL.

The first thing you notice when you slip on one of Twillory's Performance undershirts is how cool and silky it feels against your skin. It only gets better as the day goes on, since it helps keep you feeling cool and fresh no matter what the weather throws at you. The fabric is a cotton-rayon-spandex blend that's breathable and does a great job wicking sweat. The brand's known for its performance menswear, and they bring the same mindset to their undershirts. 

These tees have plenty of stretch and are thin enough to even go under a polo without added bulk. The Performance tee has plenty of length in the torso, so it stays tucked in, and it doesn't show through a white cotton dress shirt. You can choose between a crew neck or V-neck. The brand also offers a tonal version that you can't detect even under white summer-weight linen shirts. 

Read our full review of Twillory's performance dress shirts here.

If you are apt to sweat a lot, Ejis has you covered with the brand's Sweat Proof V-neck, specifically designed to keep your dress shirts dry and sweat-stain free. They make the undershirt from a soft micro-modal that's light and breathable. The tees' secret weapons are ultra-absorbent underarm pads that are waterproof and prevent any sweat from getting through to your dress shirts. 

The tee also has anti-odor properties using silver nanotechnology that fights scent at the source. And besides the sweat-proof properties, it's tagless, has a collar that lays flat, and is cut long enough to stay tucked in. The V-neck allows you to leave one button undone on your collared shirt. It's not a cheap product, but it will help save your expensive dress shirts from getting sweat stains and ending up in a landfill.

You probably know SPANX for its women's shapewear, but the Atlanta-based company also makes men's undergarments in sizes from small to XXL. The SPANX Zoned Performance Compression V-neck helps give men a more toned look under their dress shirts by targeting the torso and abs, toning the chest, and helping with your posture. 

They make the undershirt from a nylon-spandex blend that offers ease of movement, wicks sweat, and dries quickly. It also features mesh zones at the pits and back to help keep you cool. If you've been slacking at the gym or just need a boost of confidence, SPANX has you covered.

What is the main purpose of wearing an undershirt?

Undershirts are typically used as a barrier between your skin and your shirts. They help prevent your shirt from soaking up your sweat, which can lead to discomfort and an unwanted aesthetic.

Why does the color of my undershirt matter?

While white undershirts are the standard color, a darker- undershirt is the way to go with lighter colored dress shirts, especially if they're summer-weight, like a thin cotton or a linen. Colors like gray or black are much less visible than traditional white undershirts under thinner, white or light-colored fabrics.

How do I choose between a crewneck and a V-neck?

If you're wearing a tie or buttoning your dress shirt all the way up, a crew-neck undershirt is your best bet. But if you, like so many others these days, are going for a more casual look with your dress shirt unbuttoned at the neck, a V-neck should be your go-to. This style of undershirt stays under wraps for a cleaner, more elegant appearance.

Is it worth spending more on undershirts?

Yes. As with a lot of things, you often get what you pay for. In our experience, high-quality undershirts will last longer. They have stronger seams, are often pre-shrunk, so they don't shrink further, and keep their stretch. As an essential that will get regular wear and washes, it's important to pick one that will last.