Cheaper hiking socks are usually made from polyester mixed with other synthetics, like nylon, acrylic, and elastane. Whereas more expensive ones from merino wool mixed with a bit of synthetics. But is paying more for merino wool socks really worth it? Won’t polyester socks perform similarly well?
In this article, I’ll explain the differences between polyester and merino wool socks. I’ve hiked with both, so I’ll explain for what occasions each material is better.
What Is Polyester And What Are Its Benefits In Hiking Socks?
Polyester is a synthetic fabric that’s widely used in apparel, especially sports clothing. It’s also often used as the main fabric for hiking socks.
Benefits of Polyester
- Absorbs less than 1% of its body weight in water. It’s one of the most water-resistant fabrics out there
- Very affordable
- Abrasion and tear-resistant
- Tight-fitting and strong fabric
Disadvantages of Polyester
- Not very breathable
- Absorbs oils, which means that it starts to smell bad very quickly
- Heavy
- Doesn’t have good insulation properties
- Can cause abrasions if rubbed against the skin
What Is Merino Wool And Why It’s So Widely Used In Hiking Socks?
Merino wool is wool obtained from a single breed of sheep called Merino, usually grown in New Zealand and Australia. It has a much thinner yarn diameter than wool, which greatly improves its properties over regular wool. It’s the most popular choice of material for various pieces of hiking gear, including socks, base layers, hats, and gloves.
Benefits of Merino Wool
- Keeps you cool in summer and warm in winter
- Lightweight
- Odor resistant
- Soft against the skin
- Breathable
- Doesn’t feel abrasive and keeps insulation properties when wet
Disadvantages of Merino Wool
- Expensive
- Not very durable
- Dries slowly
- Doesn’t offer a very tight fit
Polyester Vs Merino Wool Characteristics In Hiking Socks
Moisture Wicking
Merino Wool does a much better job of keeping your feet dry while hiking compared to polyester. That’s because merino wool and wool in general absorb vapor, but don’t like larger water particles. When your feet are sweating, merino wool socks absorb the sweat in its vapor form and release it through the outer layers of the sock over time before larger droplets can start to form. This makes your feet stay dry while doing active sports. With polyester, the sweat builds up much faster (unless it’s a very thin and breathable sock), and your feet get damp even though the sock itself is dry.
Drying Time
When merino wool socks get wet, they dry much slower compared to polyester socks. That’s because merino wool can absorb much more water than polyester (35% vs less than 1% of its dry weight). That’s why polyester socks are more often used when hiking in extremely wet environments.
Odor Resistance
Polyester is one of the worst fabrics for odor resistance while merino wool is one of the best. That’s because polyester absorbs natural oils from your body, and keeps them inside the fabric, where they multiply and the sock starts to smell bad very quickly. Merino wool also absorbs oils and bacteria, but because the sock offers a much drier environment, bacteria don’t multiply in there as quickly, so the socks stay smelling fresh for longer. From my own experience, polyester socks and t-shirts start to smell bad 2x quicker compared to merino wool.
Softness
Although merino wool isn’t itchy (unlike regular wool made from thicker-diameter wool fibers), polyester feels a bit softer on the skin when dry. But when both of these fabrics get wet, merino wool feels a bit softer than polyester.
Blister Resistance
From my own experience, merino wool socks vastly outperform polyester socks in blister resistance. That’s because blisters tend to form in the presence of water (or sweat), bacteria, and when there’s some form of abrasion happening on the skin. Merino wool is naturally soft, even when wet, it naturally dries out all the sweat while hiking, so the skin of your feet stays dry, and it’s antibacterial. When I switched to good merino wool socks, I pretty much stopped having any blisters.
Insulation
Merino wool is much better than polyester at keeping your feet warm. That’s because merino wool contains a lot of dry air inside, which acts as a natural insulation layer between your skin and the outside.
Breathability
Merino wool is more breathable than polyester. However, when polyester is made into a thin form with lots of gaps in between the fabric, it can also be really breathable.
Durability
Polyester is more durable than Merino Wool. That’s because merino wool has very fine yarns and fibers, and polyester is synthetic, which is much stronger. Over time, 100% polyester socks will outlast similar 100% merino wool socks at least twice as long.
Cost
Polyester is cheaper than Merino wool. That’s because it’s manufactured from readily available plastics, whereas merino wool can be made only from a specific breed of sheep, grown only in certain parts of the world.
Most Good Hiking Socks Are Made From A Mix Of Merino Wool And Nylon
Usually, good hiking socks aren’t made from 100% polyester or 100% merino wool. That’s because each fabric has its own benefits and disadvantages, and when you combine them together, you get the best of both worlds.
Also, not all hiking socks are blended with polyester. In fact, most hiking socks are made from nylon, which has very similar properties to polyester, only it has much better odor resistance at the cost of slightly worse water resistance.
The Best hiking socks are usually made from 40-70% merino wool, 30-60% synthetics (nylon or polyester), and 1-5% elastane, spandex, or Lycra. I’ve found this material blend to perform the best for thru-hiking.
Frequently Asked Questions
Which hiking sock material is better in winter – polyester or merino wool?
Merino wool is a much better insulator than polyester, which will keep your feet warm. It’s also thermoregulating, which means that in bulky winter boots, your feet won’t sweat as much. This makes it the ideal material for winter hiking socks. For winter hiking socks specifically, you should choose socks with a higher merino wool content, somewhere around 50-80%. You should also choose socks with midweight or heavyweight thickness, and they shouldn’t feel too tight against your skin, otherwise, they will restrict blood circulation and make your feet cold.
Read Next: Are Polypropylene Socks Good For Hiking?
Which hiking sock material is better in summer – polyester or merino wool?
For summer hiking, merino wool socks are better, but thin, 100% polyester/synthetic socks are also fine. When polyester is weaved very thinly, it’s breathable enough, and your feet shouldn’t get sweaty over time. Another bonus for polyester is that it’s a very strong fabric, which can be made into compression socks, so it’s helpful for people whose feet tend to swell after long hiking days.
Thin 100% synthetic socks are also good to use in winter as liner socks underneath a thicker pair of merino wool hiking socks. This combination can achieve even better insulation and blister resistance.
But in general, the best summer hiking socks will be made from 30-60% merino wool mixed together with synthetics.
Which hiking sock material is better for sweaty feet – polyester or merino wool?
For sweaty feet, merino wool is a much better choice than polyester when it comes to hiking socks. That’s because merino wool does a much better job at keeping the skin of your feet dry due to its impressive thermoregulation properties. Polyester isn’t very breathable and it doesn’t absorb much water, which means that the sweat will mostly stay on your skin.
What are the best merino wool hiking socks?
My personal favorite merino wool hiking socks are the Silverlight Merino wool hiking socks, which are made from 53% merino wool, 40% nylon, 5% silver yarns, and 2% spandex. I finished a 500-mile thru-hike with them (one crew pair and one ankle pair), and I didn’t get a single blister on my feet. Even after 2 years of using them regularly, they’re still in a very useable condition. They dry quickly, my feet don’t sweat in them, and they even have slight compression built into the fabric.
What are the best polyester hiking socks?
One of the best polyester hiking socks is the Darn Tough Coolmax Micro Crew Cushion hiking sock. It’s made from 53% Coolmax, 37% nylon, 5% acrylic, and 3% Lycra. Coolmax is made from 100% polyester, but it has slightly better breathability and moisture-wicking properties due to a different manufacturing process. These are a good option for late spring, summer, and early autumn hiking, because they’re very breathable and thin, while still providing a good amount of cushioning and comfort. Many people choose this sock because it’s vegan or due to wool allergies.