The Best Sleep Sacks to Keep Your Baby Cozy—and Safe

Like Goldilocks’ porridge, some baby products get it “just right”—and the Halo SleepSack is one of them. This reliable, straightforward sleep sack is “so easy to use and helps my baby fall asleep,” says one Babylist parent. It’s also well-priced, soft and available in a wide range of sizes and colors. I’ve tried a lot of sleep sacks over the last ten years, but there was always a Halo in rotation at my house.

The Halo SleepSack is made from cotton, so it’s just the right amount of cozy; it will keep your baby warm, but not too warm, across a range of temps. The hip-healthy design allows freedom of movement for your baby’s legs and it’s available in smaller sizes for younger babies all the way up through an XL size for toddlers to about two years old.

The zipper on this sleep sack opens from the bottom. While this does make diaper changes easier, some parents note (myself included) that this can make getting a wriggly larger baby or toddler into the sack a bit of a challenge. If you live in a cooler climate, or if your winters get chilly, Halo makes a just as affordable fleece option to keep your little one extra cozy. There's also a soft bamboo version that does feature a double zipper (and a higher TOG), just note it's more expensive than the cotton option.

Most newborns like to be swaddled, but not all. If that’s the case with your baby, as it was with one of my boys—or if you’d simply prefer to skip the traditional swaddle and try something else—the Love to Dream Swaddle Up is an ideal option. Part sleep sack and part swaddle, this creative hybrid is a great option for babies who may not like the tightness of a traditional swaddle blanket but aren’t quite ready for the freedom of a sleep sack. The Swaddle Up lets your little one sleep with their arms up, a natural position that also gives them access to their hands for self-soothing.

“We tried all sorts of swaddles: traditional, Velcro, zip, and all presented their own set of issues—baby getting free, loud Velcro rip during late night diaper changes, etc,” one parent shared in our Most Loved Products survey. “We tried Love to Dream and our girl finally started those long overnight stretches of sleep. It was a game-changer. It kept her snug without restricting her movement.”

This sleep sack swaddle is easy to use, soft and breathable, and goes on (and off) in seconds thanks to the two-way zipper. Just keep in mind that, unlike traditional arms-out sleep sacks that can be used well into toddlerhood, you’ll need to ditch this one as soon as baby starts showing any signs of rolling over. You’ll also want to pay attention to sizing. Because it’s designed to be used with baby’s arms up, you need a snug fit, especially around the neck, to ensure there isn’t any fabric making its way up over your baby’s mouth or face.

If there’s ever been a baby product that I wish came in adult sizes, this is the one. Kyte Baby’s sleep sacks are THE softest around; I’ve tried them all, and nothing else compares. Parents agree, consistently calling them out as “very soft” and “so comfortable.” “My son absolutely loves his Kyte sleep sack,” one mom told us. “It has truly become his comfort item.” My toddler would concur. He’s four and sleeps in a bed, but won't part with his tried and true Kyte Baby sleep sack and snuggles with it almost every night.

Kyte Baby’s soft factor comes from the brand's sustainable bamboo fabric with just a touch of stretch. And speaking of material, the sleep sacks come in a range of TOGs, from a very thin 0.5 all the way up to a thick 2.5. (TOG = Thermal Overall Grade, which indicates how much heat the fabric retains. You’ll want a lower TOG in a warmer sleeping environment and a higher TOG for a chillier one.) Babylist parents said they like the option of different TOGs based on the season or the sleeping environment, and appreciate the peace of mind of knowing their baby is sleeping comfortably regardless of the temperature.

The biggest downside to Kyte Baby’s sleep sacks is price: they’re expensive. They’re also on the delicate side. While they do hold up in the wash, I wouldn’t recommend putting them through a heavy-duty cycle multiple times a week. They’re also air-dry only, so you’ll want more than one on hand if this is going to be your day-to-day sleep sack as they take about a full day to dry.

If you value sustainability and organic materials, this wearable blanket from Tiny Kind is for you. It’s made from 100% GOTS-certified organic cotton. The inks are organic and non-toxic, and the factory's boxes are made from recycled fabric straps converted to paper pulp.

This sleep sack features a two-way zipper for easy on and off, and there’s plenty of room in the lower half for your little one to kick and move their legs around freely. It's a 1.0 TOG, so it works best for mid-range temps. Just note you'll need to find a new option once your baby grows, as the Tiny Kind wearable blanket maxes out at about six months for most babies.

If you live somewhere with cold winters, or you’re just a big fan of Arctic-like sleeping conditions (🙋🏻‍♀️), you’ll want an extra-warm sleep sack to keep your little one comfortable. The ergoPouch is as close as you can get to a baby-safe luxury down comforter. It’s made from thick, stretchy organic cotton and has a TOG of 2.5, so it’s suitable for rooms between 61-71°F. It’s by far my favorite sleep sack for those long, cold winter nights. While it works well through toddlerhood, I especially like it for younger babies due to the slim, stretchy fit up top that mimics the security of a traditional swaddle.

Like Kyte Baby sleep sacks, this one is also air dry only, and since it’s very thick, it takes a while to dry completely—so keep that in mind when deciding how many you’ll need. It’s also pretty pricey. For another cold-weather option, I also like Kyte Baby's 2.5 Tog Sleep Bags.

You don’t need to own a different swaddle for every season; it’s possible to be one-and-done. The Woolino sleep bag works across a huge range of room temps, from 63° up to 77°F. That’s because it’s lined with Merino wool, a material that naturally regulates body temperature. It’s warm in winter, cool in summer and can be your go-to sleep sack all year long.

Unlike other sleep bags, the Woolino is universally sized and can be used from about two months through two years old. It’s also known for its durability, since Merino wool is machine washable and holds up well over time. So while it’s expensive—it’s the priciest sleep sack on our list by far—it’s worth it, according to many parents. “It’s been in constant use for three+ years with our two kids and is still in great shape,” one parent told us. “I give all my friends one as [a] baby gift now.”

The one thing to note about the Woolino is that while the top adjusts to fit babies as they grow (there are snaps on the underarm area of the sleep sack to adjust the fit), the bottom portion remains the same size. This means that on a smaller baby, all of that fabric can look and feel a bit overwhelming. It’s still a safe fit, but something to know so it doesn’t catch you by surprise.