Odlo's Performance Wool Base Layer set has an interesting blend of mostly merino wool with a touch of polyester, polyamide, and elastane. The result is a set of thermal underwear ideal for most winter sports and activities. “These layers fit like a second skin,” our tester said. “I have other wool base layers from Ibex, Smartwool, and Icebreaker; these are as good, if not better, with nice stretch without feeling constricting.” The zip reaches to just below the belly button, so this is easy to step in and out of, plus it has ankle cuffs to ensure you feel extra cosy. It has a snuggly hood too. Our favourite features? Not only is this women’s onesie ridiculously soft, it has cute ears on the hood and full length legs that are just begging to be worn with booty slippers to complete the outfit. Finally, we cross-referenced all of the above information to find the best onesies for women that had won the most accolades and recommendations across the board to bring you a selection of the best ones at various price points. We think there’s something here for everyone. Why you should trust us Touching on the price of this, it is the most expensive in our edit, but for a luxury treat that you’ll treasure all winter long, we think it can be justified.

As Martin Lewis said, it’s easier to heat the person than the home, so if you’re home alone during the day, rather than spending money heating the whole house, it’s worth layering up in a onesie to conserve warmth.Firstly, do you want a hood? Many onesies come with novelty hoods with ears, while others have a simple hood. A hood makes your onesie extra warm and snuggly, though it does look more casual if you’re planning to wear it to keep warm while working from home. Like Patagonia’s Capilene line, Kari Traa’s Rose thermal underwear set is a classic. Constructed with 100 percent merino wool, these midweight base layers also feature four-way stretch, which our tester found moved well with her body. Our tester, who has skin that’s very sensitive to traditional wool, found the merino wool “very pleasant to wear.” In particular, we appreciated the breathability and insulating warmth that makes the material so popular. Look at the sleeves and ankles of your onesie. Many come with elasticated cuffs to keep you warm, but if you think you’ll find that annoying, opt for a looser fit onesie.

Arc’teryx’s Rho top works well for lower-output activities in colder temperatures. Our tester found this the perfect base layer for walking the dog in New York weather when temperatures were in the upper 30s. The proprietary “Torrent” fabric impressed our tester with how cozy and comfortable it was, while also excelling at temperature and moisture regulation. The “Polygiene” odor control also helps to keep you smelling fresh on the trail. Choosing the best women’s onesie is down to personal choice, but there are a few things to consider before investing in your cosiest outfit yet. Also like the Capilenes, the Rose set has a slim, athletic cut. Our tester tried two sizes and appreciated the difference in each. “The bigger size has a bit of wiggle room while still being fitted, and the smaller provides slight compression and is perfect for layering.” We also appreciated the half-zip design for the top layer as it provides a bit more versatility and a way to release heat while participating in higher-output activities.Still, these are not the most breathable base layers we tested, which is one reason why we recommend them for lower-output activities, like light hikes, dog walks, and trips to brunch. That said, even with the higher cost, our tester still highly recommends them for lounging on winter days and for light activities. Sure, you’ll look like you’re off to a teddy bear’s picnic in this super-soft onesie, but you’ll also be cosier than you’ve ever been. Merino wool isn’t the same as the kind your grandma uses for knitting. It’s very soft and comfortable. That said, testers who were extra sensitive to itchy or irritating fibers did report some issues with a couple of the merino wool thermal underwear sets we tried. If you tend to get irritated by wool, opt for a synthetic alternative like the Under Armour option above. Fans say it’s fantastic to wear on top of pyjamas for an extra cosy layer, plus they praise it for staying just as fluffy when washed. One reviewer even noted it’s so cosy they don’t need to put the heating on - the ultimate praise when energy bills are soaring.

Our favourite features? Fans praise how soft and cosy it is, with many impressed by the bright colour, too. Our favourite features? If you want a warm, snuggly onesie which can also double as fancy dress option, look no further! Sizes: XXS - XL | Colours: Navy | Materials: 79% Lenzing™ Ecovero™ Viscose, 19% Polyester, 2% Elastane Reasons to buy Since 1982, our company has been carefully manufacturing our flagship Extra Warm Thermal Underwear range at our own factory in Leicester (England, UK). In addition to this, we also offer some competitively priced options which are made at our foreign facilities, but everything continues to be proudly designed and quality controlled in the UK.

5. Best patterned onesie for women: Hunkemoller Leopard Print Onesie

Absolutely, there are endless options for onesies for adults, as shown in our edit of the best onesies for women. You can even buy matching onesies for the whole family, be it for Christmas, birthdays or family trips. How onesies can help cut heating bills

Proving that onesies can be stylish as well as snuggly, this super-soft jersey onesie is the ultimate in luxury loungewear. The drawstring waist means it looks a little smarter than your average onesie, but is still super comfortable when you fancy a really lazy day. Reviewers of Hunkemoller garments note that the sizes come up small, so if you’re keen to layer this, invest in a larger size to be sure it will fit.For any expectant or new mums, fans of this onesie rate it for taking in your hospital bag and wearing in those early newborn days. “It’s really soft and super comfy, easy for breastfeeding and fits well around my bump,” one reviewer wrote. Another new mum wrote: “I bought it as a postpartum treat and it's well worth the money.”