Merino polo size guide: get the fit right

Buying a merino polo online should feel easy. But sizing can be the one thing that turns a brilliant everyday staple into the top-drawer regret - too tight across the chest, sleeves that ride up, or a length that refuses to stay tucked.

This merino polo size guide is built to stop that happening. It’s practical, fit-first, and written for real life: office days, travel weeks, golf rounds and everything in between.

Why merino polo sizing feels different

Merino isn’t your average cotton pique. It drapes differently, it moves with you, and it’s often worn more ways - solo in warm weather, layered under a jacket when the temperature drops. That means the “right size” depends on how you actually wear your polos.

Merino also tends to look smarter when it fits cleanly. A polo that’s too big can look sloppy fast because merino hangs, rather than holding a stiff shape. Too small and you’ll feel it every time you sit down, reach for a bag, or spend a day in humidity.

The goal: a fit that skims the body, stays comfortable when you move, and still looks sharp after hours of wear.

мерino polo size guide: the three measurements that matter

You can guess your usual size and sometimes get lucky. If you want to get it right on the first go, measure three areas. Use a soft tape measure, stand naturally, and don’t suck anything in - you’re buying a polo, not auditioning.

Chest (the make-or-break measurement)

Measure around the fullest part of your chest, under your arms, keeping the tape level. If you’re between sizes, chest is usually the deciding factor because it affects comfort, button placket sit, and whether the polo pulls when you move.

A good merino polo fit gives you a bit of breathing room without billowing. If the fabric strains across the chest or the buttons gape, size up. If you can pinch a big handful of fabric at the sides, size down.

Shoulder width (for a clean, put-together look)

Shoulders are where “close enough” shows. The seam should sit roughly at the edge of your shoulder - not halfway down your upper arm, and not creeping up towards your neck.

If you go too small, you’ll feel tightness when driving or typing all day. Too big and the whole polo looks borrowed.

Length (tuck, untuck, and travel reality)

Think about how you’ll wear it. If you wear polos untucked most of the time, you want the hem to hit around mid-hip and sit flat, not flare. If you tuck for work, you need enough length so it stays put when you reach overhead.

A quick check: raise your arms like you’re putting luggage in the overhead locker. If it turns into a crop top, you’re one size (or one cut) off.

Choosing your fit: slim, regular, or relaxed?

“True to size” is only useful if you know what the brand means by it. With merino polos, fit comes down to shape preference and use case.

Slim fit suits you if you want a sharper, closer silhouette and you’re mostly wearing it with chinos, tailored shorts, or under a blazer. It should follow your body without clinging. If you’ve got broader shoulders or a bigger chest, slim can still work - you’ll just want to size based on chest first, then check shoulder placement.

Regular fit is the safe all-rounder. It gives you room through the torso without looking boxy and tends to be the easiest choice for work-to-weekend wear. If you’re building a small wardrobe of repeat-wear staples, regular is hard to beat.

Relaxed fit is for airflow and ease. Great for hot climates, travel days, and anyone who hates that “pulled tight when I sit” feeling. The trade-off is that too much ease can look casual fast, so focus on getting the shoulders right.

Men’s merino polo sizing: what to prioritise

Most men get sizing wrong in two places: chest and sleeves.

Start with chest. If you’re between sizes and you want a cleaner look, choose the smaller size only if you can move freely without pulling at the buttons. If you want comfort for long days, golf swings, or you run warm, go up.

Sleeves should sit mid-bicep and not grip. Merino feels soft, but a too-tight sleeve will annoy you by midday. Too loose and it can look like a gym tee pretending to be a polo.

If you’ve got a longer torso, don’t just size up for length - you’ll end up with shoulders and chest that look oversized. Look for a cut that offers a touch more length or is designed to be worn untucked.

Women’s merino polo sizing: shape, bust, and arm comfort

Women’s sizing has an extra layer: how the polo sits through the bust and waist without pulling.

Measure bust first and choose a size that sits flat across the chest. Gaping buttons and diagonal pulling lines mean it’s too small. If you size up to fit the bust and the waist feels loose, that’s not a “you problem” - it’s just how that cut is graded. In that case, consider a fit that’s designed with a bit more shaping, or accept a slightly more relaxed drape for comfort.

Pay attention to armhole comfort. A polo can fit in the bust but feel restrictive under the arms when you drive, work at a desk, or carry a bag. If the armhole feels high and tight, try the next size up.

Length matters too. If you wear high-waisted jeans or skirts, you may prefer a slightly shorter, cleaner hem that doesn’t bunch.

Layering changes your size

Here’s the honest truth: if you plan to wear your merino polo under a jacket most of the time, you can usually go closer to the body without it feeling “too much”. If you plan to wear it as your only top in warm weather, you might prefer a touch more room for airflow.

If you’re using it for travel, think about day three. Slightly more ease through the torso can feel better after a long flight, a big walk, or a big meal.

The two most common sizing mistakes (and how to avoid them)

The first is sizing up because you’re worried about shrinkage. Quality merino is generally designed to be machine washable, but you still need to treat it sensibly. Follow care instructions, keep water cool to lukewarm, and avoid blasting it on high heat. Don’t buy a size too big “just in case” - you’ll lose the smart look that makes merino polos such good value.

The second is judging fit while standing perfectly still. A polo that looks fine in the mirror can feel wrong in motion. When you try it on, sit down, reach forward like you’re on a laptop, lift your arms, and twist at the torso. If it pulls at the buttons, rides up dramatically, or digs into your underarms, it’s not the right size for everyday wear.

Between sizes? Use this decision rule

If you’re stuck between two sizes, decide what you care about most.

If you want a sharper look for work, and you don’t mind a closer fit, go smaller - but only if the chest and shoulders sit cleanly with no strain.

If you prioritise comfort, travel, warmer weather, or you’re buying a polo you’ll wear multiple days in a row, go larger for ease.

If you’re broad in the shoulders but slimmer at the waist, you may need to size for shoulders and chest, then accept a little extra drape through the midsection. That’s still better than shoulder seams sitting in the wrong place.

Buying online without the stress

Online shopping should come with a safety net. Look for clear measurements, real customer feedback, and a returns window that lets you try the polo properly - not just a two-minute mirror check.

If you want a no-fuss option built around everyday merino performance, The Merino Polo is set up for confident online buying with straightforward sizing, strong review proof, and a 45-day returns policy. That’s the kind of risk reversal that makes getting the right fit a lot less dramatic.

A fit that stays fresh all day

A merino polo earns its place when you forget about it - no constant adjusting, no collar sitting weird, no tightness that builds over a long day. Get the size right and you’ll reach for it more often, pack it more often, and wear it longer between washes. Choose the fit that matches your life, not a label, and you’ll feel the difference every time you put it on.