Heatwave Men's Thermal Long Sleeve Top Review: cheap, warm, but watch the sleeves

I’ve been wearing these Heatwave men’s thermal long sleeve tops as basic winter armour – under hoodies, work polos and football shirts. Nothing fancy here: it’s a pack of 2 black thermals that are meant to keep you warm without costing a fortune. I grabbed them mainly for cold commutes and standing around at weekend matches, where you’re just slowly turning into an ice cube.

My expectations were simple: I wanted something that doesn’t itch, doesn’t feel like plastic, and actually adds noticeable warmth. I’m not after gym compression gear, just a normal base layer that feels like a slightly thicker T‑shirt. On paper, these tick a lot of boxes: cotton/poly mix, 0.45 TOG rating, good reviews on Amazon, and made in the UK.

In real use, they do what they’re supposed to do: they keep you warm. You put one on and you feel that extra layer of heat pretty fast, especially if you’re sitting still or outside in the wind. They’re not magic, but compared to just a normal cotton tee, the difference is clear. You don’t get that constant chill on your arms and back.

They’re not perfect though. The main issues for me are around the fit and what happens after a couple of washes. The body stays fine, but the sleeves can get short, and if you’ve got long arms, you’ll notice it. So overall, good budget thermals, but with a few caveats you need to know before you pile your basket with them.

On value, these are good bang for your buck if you just need basic warmth and don’t care about brand prestige. You’re getting two tops in the pack, and for what they cost, the warmth and comfort are honestly decent. You’d easily pay the same or more on the high street for a single branded thermal that doesn’t actually feel that different when you’re just sat in a cold room.

The product has a 4.2/5 rating with over 12,000 reviews on Amazon and sits high in the thermal category, which lines up with my feeling: most people are happy because it does the simple job of keeping you warmer without breaking the bank. If you wear them every day in winter under work clothes, they basically pay for themselves in comfort pretty fast.

The catch is the compromise on longevity and fit. If you’re picky about sleeve length or you hate any shrinkage, you might find them a bit frustrating. In that case, spending more on a better fabric mix (with elastane or merino) could be worth it. But if you’re like me and mainly want cheap, functional layers you can rotate through and not worry about too much, these sit in a nice sweet spot.

So in terms of value, I’d say: good purchase for everyday winter use, especially if you’re okay with sizing up to hedge against shrinkage. Not the best choice if you want something that’ll look and fit like new after loads of washes, but as a practical, low-cost way to stop shivering, they’re hard to argue with.

The design is proper no-nonsense. Solid black colour, ribbed texture, straight hem, ribbed cuffs, and a rounded high neck. The ribbed construction is actually useful: it helps the top sit closer to the body without needing stretchy Lycra. It gives a slight hugging feel without turning it into tight sportswear. Under a shirt or sweatshirt, it just looks like a normal base layer and doesn’t print through much.

The neckline is something I paid attention to. It’s high enough to keep your upper chest warm, but not so high that it sticks out of most T‑shirts. Under a football top, it looks like you’re just wearing a long sleeve base layer, which is exactly what it is. No V‑neck option though, so if you wear open shirts a lot and hate seeing the thermal at the collar, this design might annoy you.

The sleeves are where the design shows its limits. The ribbed cuffs are good because they keep the sleeves from flapping around, but the overall sleeve length is just on the edge for anyone with long arms. On me, new out of the pack, they were okay – not generous, not short, just okay. After washing, they crept up a bit, and suddenly the cuffs were sitting a couple of centimetres above the wrist. Not tragic, but you feel it when you stretch your arms forward.

Visually, there’s nothing exciting, but that’s kind of the point. These are clearly designed to disappear under other layers. If you want colour matching with team kits or work uniforms, at least the range has multiple colours, but this specific set in black is just that: plain black thermals that focus on function, not looks. For an underlayer, I’m fine with that, but if you want something you can comfortably wear on its own in public, the cut and finish are a bit too “underwear” for my taste.

On comfort, these tops are pretty solid for daily use. First thing I noticed was that they don’t itch at all, even on bare skin. I’ve worn them straight over my skin under a work polo for 8–10 hour shifts, and I never felt the urge to take them off. They feel like a slightly thicker, softer T‑shirt that happens to hold heat better. No scratchy tags or annoying seams rubbing under the arms.

The warmth is the main comfort benefit. With a 0.45 TOG rating, they actually trap a fair bit of heat. Sitting in a cold office or standing around watching a match, you feel noticeably less chilled, especially on the arms and lower back. Under a short-sleeve football shirt, it kept me warm enough that I wasn’t thinking about the cold the whole time, which is basically all I want from a thermal.

Fit-wise, they’re described as fitted but not skin-tight. On me, that translated to a slightly hugging feel around the torso and shoulders, but still enough room to move. If you’re between sizes, I’d seriously consider going up one, especially if you’re worried about the sleeves shrinking. One Amazon user said their XL grey felt more like a large compared to the white – so sizing can vary slightly between colours. On my black set, large was fine, but after washing, it went from “comfortable” to “a bit snug”, especially around the arms.

The only real comfort issue is again the sleeve length after washing. When the cuffs creep up your forearms, you get that annoying cold patch between glove and sleeve, or between thermal and outer layer. It’s not unbearable, but it’s noticeable and slightly defeats the point of a warm base layer. So comfort is good overall – warm, soft, breathable enough – but if you’re tall or have long arms, you may find them less comfortable long term unless you size up.

Depending on where you look on the listing, the composition is listed as 60% cotton / 40% polyester or 50/50, but in the hand it feels like a typical cotton-heavy thermal. The inside and outside both feel more like a thick T‑shirt than like shiny synthetic sports gear. That’s what I wanted – I’ve tried those 90% polyester thermals before and they felt plasticky and built up static. These Heatwave ones feel more natural on the skin.

The fabric weight is medium, which means they’re not ultra-thin like some high-tech base layers, but not as thick as a sweatshirt. Under a normal shirt or work polo, it doesn’t feel bulky. You still move freely, and you don’t get that stiff feeling around the shoulders. The ribbed knit traps a bit of air, which adds to the warmth without needing a heavy fabric.

The big downside is shrinkage after washing. I followed the instructions (30°C machine wash) and line dried them. The body length stayed mostly fine, maybe a tiny bit shorter, but the sleeves definitely pulled back a bit. One of the Amazon reviewers had the same problem – sleeves shrinking a couple of inches. On my side it wasn’t quite that bad, but it was noticeable enough that if you’ve got long arms, you’ll feel the difference.

Overall, the material is decent for the price: soft enough, not itchy, warms up quickly once you’ve had it on for a few minutes. But it’s not premium fabric. It doesn’t have stretch like elastane, and you can tell that after a few washes the shape isn’t perfect anymore. For budget winter layers, the material gets the job done, just don’t expect them to age like expensive merino or branded sports baselayers.

Durability-wise, I’d call these average but acceptable for the price. Stitching out of the bag is neat: no loose threads, no holes, seams are straight. After several washes, I didn’t get any bursts or unraveling, which is good. The fabric itself still feels intact – no thinning spots or pilling after a few weeks of use.

The main durability issue is shape retention. Like that Amazon review mentioned, the sleeves are the weak point. After one or two 30°C washes, you notice they don’t sit as low on the wrist as when new. On my tops, the body length held up reasonably well, so they still tuck in fine, but the sleeves definitely shortened. It’s not a total disaster, but it does make them feel a bit cheaper over time.

Compared to more expensive thermals I’ve tried (like branded sports baselayers), these don’t age as nicely. Those usually have elastane and better stretch recovery, so they snap back into shape. The Heatwave tops are non-stretch cotton/poly, so once they shrink or warp a bit, that’s basically the new shape. That said, for something you’re paying budget money for and wearing under other clothes, I don’t expect them to last five winters.

In practice, I think you’ll get at least one solid winter out of them, maybe two if you’re careful with washing (cool wash, avoid the dryer). If you hammer them in hot washes and tumble dry, expect faster shrinkage and a tighter, shorter fit. So durability is okay, but not a strong point. They’re more like consumable winter gear than long-term investment pieces.

Out of the bag, it’s as basic as it sounds: you get a pack of two long sleeve tops, same size, same colour (in this case black). No fancy branding, no big logos, just plain ribbed thermals. Honestly, that’s what I want in a base layer – something that disappears under whatever else I’m wearing. The listing says they come in white, blue, grey, navy, charcoal and black, but my set was just solid black with a simple neck label.

The cut is described as comfort fit, and that’s about right. It’s not tight like compression gear, but it’s not baggy either. It follows the body without clinging to every lump. I wore mine under a regular shirt at work and under a football shirt at a match; in both cases, you couldn’t really tell I had another layer on. No bulky seams, no weird bunching around the waist.

Each top is a standard length – it comes down past the belt line enough that you can tuck it in and it stays put. That’s important because there’s nothing worse than a thermal that rides up and leaves a cold strip on your lower back. The neck is a rounded high-ish crew neck, so it sits just below most shirt collars. It’s not a low scoop that lets in drafts, but it doesn’t choke you either.

In terms of first impression, the product is straightforward: two mid-weight thermals, no surprises, no accessories, no gimmicks. You buy it, you get functional winter underwear, that’s it. If you want something stylish to wear on its own, this isn’t it. These are clearly meant as underwear baselayers, and they look and feel like it – which, for the price, is exactly what I expected.

In terms of pure effectiveness, these tops do the main job: they keep you warmer than a normal cotton tee. I’ve worn them in a few different situations: cold morning commutes, sitting in a chilly office, walking the dog in wind, and standing still at a football match in a short sleeve shirt over the top. In all those cases, I could tell the difference when I wore the Heatwave top versus when I didn’t.

The 0.45 TOG rating isn’t some magic number, but you can feel the extra insulation. The ribbed structure traps air close to your skin, and because it’s cotton-rich, it doesn’t feel sweaty straight away. Under a hoodie and jacket, I stayed comfortable even in proper winter temperatures. It’s not arctic gear, but for UK-style cold, it’s absolutely fine as a base layer.

Where it’s less effective is over time if you’re moving a lot and sweating. The fabric doesn’t have fancy moisture-wicking like sports brands, so if you’re running or playing intense sport, it can feel a bit damp. For casual use, dog walks, commuting, watching a game, or working in a cool warehouse, it’s more than good enough. One Amazon reviewer even mentioned using it as a base layer for football and being "warm as toast" at a match, which matches my experience in the stands.

The only thing that slightly reduces its effectiveness is again the sleeve shrinkage. When your wrists aren’t properly covered anymore, you lose some of that full-arm warmth. It doesn’t ruin the product, but it does mean they work best in the first few washes, then you start to notice the compromise. Still, as an everyday budget thermal, in practice it keeps the cold off well enough that I keep reaching for it when the temperature drops.