Merino Wool vs Poly Blends – Ultimate Fabric Faceoff for Travel

Shawn Forno

Wool base layers, (multiple) wool socks, wool beanies, wool t-shirts are all part of my wardrobe—heck, I even have wool pants. I love wool travel clothes. Merino wool is my go to choice for most travel clothing, but it’s not perfect, and it’s pretty pricey.

Fabric technology (yes, that’s a thing) has come a long way in the past decade. Travel clothing is getting lighter, stronger, and cheaper, as well as more sweat, stain, and dirt resistant. There’s some pretty great stuff out there.

When it comes time to purchase your next big travel item, you have to ask which is better: the quality and reliability of 100% merino wool or the fit, feel, and space-age features of a polyester blend? To help you choose the right gear, we’re taking a deep dive into the differences between merino wool and polyester travel clothing.

Merino Wool vs. Polyester Travel Clothing

What is Merino Wool?

You may have heard the term “merino” a hundred times and not really know what it means. 

Simply put, “merino” gets its name from the breed of sheep that the wool comes from. Originally from Spain—not New Zealand as many people think, although there are millions of merino sheep in NZ now—merino wool is renowned for its soft feel and ultrafine fibers, as well as its incredible body temperature regulation, sweat-wicking properties, and overall performance.

The Benefits of Merino Wool

Merino wool is the Cadillac of travel fabrics. Merino feels amazing, looks great, and keeps you warm in the cold and cool in the heat (if you pick the right layer and thickness). It fights odors, wicks away moisture, and just plain gets the job done whether it’s in your sweaty boots or your base layer.

This fabric is premium travel clothing design at its finest. Once you go merino, you’ll feel the difference right away.

The Cons of Merino Wool

Merino wool is expensive, relatively fragile, and not ideal for every type of travel clothing. While it makes an amazing base layer on your skin, the wrong weight can make you heat up on the trail, while the thinnest weave just won’t last forever. 

Take merino for a test drive before you update your entire wardrobe.

Merino Wool Thickness

Merino wool varies, but it’s typically anywhere from 15-23 microns thick. One micron is 1/25,400th of an inch. To put that into perspective, a human hair is about 60 microns thick. So, yeah, merino wool is superfine.

That incredibly fine fabric gives merino its distinct comfortable feel and soft texture, and also its performance. But that ultrafine fiber comes with some fine print.

Merino Wool Weights

Not all merino is created equal. Ultra-lightweight merino might feel amazing as a base layer (it’s awesome), but that superfine feel isn’t just pricey—it’s fragile. The lighter the weight of your merino wool, the sooner it’s going to breakdown.

Merino wool base layers are notorious for wearing out faster than their polyester brethren. It’s due largely to those ultrafine fibers. If you want your wool base layer to last, bump up to something a little beefier, and maybe only get one ultrafine layer for travel days and long flights. But be careful not to overshoot it.

Merino is awesome at locking in your body heat. A thicker weave might make you heat up on a vigorous hike. I look for “Runweight” merino base layers because they’re thick enough to stand up to regular washing and wear and tear, but still soft on your skin and porous enough to let the sweat out. 

Remember, a base layer is supposed to move sweat away from your skin, not insulate your entire body. Let your jacket or next layer handle the cold.

Pro Tip: Prolong the life of your merino by skipping the dryer. Merino air dries like a champ.

The Best Merino Clothing: Base Layer and Socks

Darn Tough Merino wool blend hiking socks (61% merino)

    What is Polyester and a Polyblend Fabric?

    Polyester (polyethylene terephthalate) can be made from just about anything—cellulose, plants, optimism—but this synthetic material is primarily made from petroleum-based polymers. 

    Before you get scared of the idea of wearing oil on your body, remember that polymers are just repeating chains of molecules in a line (“poly” means “many”).

    Polyester blends are just what the name suggests—a mix of polyester and other fabrics. This typically means cotton fibers (65/35 is the most common blend, but 50/50 happens all the time), although it may include silk, rayon, lycra, nylon, and a hundred other combinations of fabrics.

    Polyester is inexpensive, wrinkle-resistant, dries quickly, and most importantly retains its color. In fact, they have to use special dyes just to get polyester to change color because it’s so difficult to alter the material makeup. And once it’s in there, it’s locked in tight.

    Case in point: I love the Bluffworks Travel Chinos. These 100% polyester pants are amazing for travel and for the rest of my life because they simply take whatever I throw at them. I bike in them, I go to work in them, I spill stuff on them all the time, and it doesn’t matter. They dry quickly in the rain and handle my sweaty commute in stride. 

    Plus, I get compliments on the vibrant “harvest gold” color of my pants all the time. And I’ve washed them a lot.

    What to Look For In a Polyblend Fabric

    Polyester blends are great if you really want to customize your travel clothing to specific situations. I always look for a little stretch in my travel clothing, particularly shirts and pants. 

    Five percent lycra, nylon, or spandex is the magic number for the right amount of give without the ’80s-looking sheen of bicycle pants.

    If tear-resistance and durability are important, go with a 50/50 polycotton blend. Polyester is more tear-resistant than cotton alone but doesn’t breathe as well. Cotton tears more easily, but stands up to abrasion better (a.k.a. washing machine cycles). 

    Cotton blends allow polyester fabrics to open up, and take a beating in the washing machine without sacrificing the tear resistance that keeps your clothes from ripping on the trail. It’s a nice marriage. Plus it won’t shrink as much in the wash.

    The Benefits of Polyblend

    Polyester blend travel clothing is cheap to buy, easy to wash, and can take a lot of abuse. It holds its color well, stretches with you as you travel, and you can tweak the fabric to your tastes, body type, temperature controls (some people just sweat way more than others), and style.

    However, the biggest pro for polyester is that it’s wrinkle-resistant and has unbeatable durability in wet, dry, hot, or cold weather.

    The Cons of Polyblend Fabric

    Polyester doesn’t feel awesome on your skin. While it’s not as comfy as merino, the right blend can get you close. 

    Seriously, don’t be afraid of polyester. Just because some style guru or travel writer has a king’s ransom in merino wool doesn’t mean your polyblend isn’t just as awesome. 

    Polyblend isn’t my top choice, but I’ve got plenty of polyblend shirts that I routinely pack. And so should you.

    The Best Polyblend Travel Clothing: T-Shirts and Pants

    However, the best travel wardrobe might just be a little bit of both merino and polyester…

    Merino Wool Polyblends

    The future of travel clothing isn’t always this vs. that. Sometimes two fabrics are just so good that they come together to create something even better. Case in point, merino-poly blend shirts. These items have started popping up, and I couldn’t be happier about them.

    The Outlier Runweight Merino Polyblend crew shirt was my go-to for my 6-week hike on the Camino de Santiago. This 50/50 blend of merino wool and “thermobuffering polyester” was the best of both worlds. Warm in the chilly mornings, but great at wicking away sweat from the hike and the occasional downpour. It kept me warm at night, cool during the day; it fit and felt like I was wearing a cloud.

    I bought two of them.

    If you want a comfy, more heavy duty merino/poly blend mid layer, look no further than the Voormi Confluence Hoodie. This thicker merino wool locks in heat, while not cooking you in your own juices. It’s the perfect marriage of robust merino, and the high tech functionality of polyester blends.


    When you invest in top quality gear—whether it’s traditional merino wool or the newest polyester hybrid—you’re investing in your ability to travel better, longer, and be more prepared for anything that comes your way. Diversify your travel wardrobe with all types of fabrics and enjoy the flexibility of travel clothing that works in any environment. 

    • Merino wool is ultrafine—typically 15-23 microns thick
    • Merino might be the best feeling base layer fabric ever, but be careful—it’s delicate
    • Polyester can blend with just about anything, from cotton to lycra
    • Polyester is wrinkle-resistant and stands up to multiple washings
    • Merino poly blends are the future of travel clothing

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