The 12 Best Sleep Sacks for Sweet Dreams
It’s natural to want to wrap baby up for bed, but putting a blanket in an infant’s crib before their first birthday is a big safety no-no. But that doesn’t mean your little one has to be cold at night or during naps. A sleep sack is a safe alternative to loose bedding. Like a swaddle, a sleep sack safely restricts baby’s legs (and sometimes arms) to keep them in a cozy cocoon all night long.
Better yet, these wearable blankets come in a variety of seasonal fabrics and fun patterns. Not sure what to look for? Here, you’ll find a breakdown of the different options and a list of top-rated brands, plus the best sleep sacks for every stage of development.
A sleep sack is essentially a wearable blanket for baby. Sleep sacks are great for newborns who fight the swaddle and older babies that have graduated beyond the burrito stage. What’s more, wearable blankets can help regulate baby’s temperature and prevent overheating.
Are sleep sacks safe?
According to the American Academy of Pediatrics (AAP), infants should be dressed in warm pajamas or a sleep sack, and placed in a sleep space free of any loose bedding or soft objects. Blankets can pose a suffocation hazard and increase the risk of SIDS. While the majority of sleep sacks are safe, you should never use a weighted option. Updated sleep safety guidlines from the AAP note that weighted sleep sacks aren’t safe for infants.
When picking out a sleep sack for your little one, Jillian Thistel—a certified pediatric sleep consultant and founder of Twinkling Stars Pediatric Sleep Consulting in Ontario, Canada—reminds parents to make sure the wearable blanket fits baby comfortably. It shouldn’t be “too big or loose (which can put little ones at risk of suffocation),” she explains. Likewise, the sleep sack should be lightweight to reduce the risk of overheating and SIDS, adds Loretta Cody, MD, a board-certified pediatrician based out of Connecticut.
How long can baby use a sleep sack?
As per Thistel, “the length of time that a baby uses a sleep sack is really dependent on the individual baby;” there’s no cut-off age or timeline. Just remember to always check the manufacturer’s guidelines and your child’s weight at the time you are using a sleep sack, says Cody.
If you opt for a sleep sack that restricts baby’s arms and chest, stop using it once baby shows signs of starting to roll over (this commonly begins around the three- or four-month mark). The good news? The AAP emphasizes that sleep sacks that don’t have a swaddle effect (and allow baby to move freely) can be used well into toddlerhood.
Wearable blankets come in all shapes, sizes and materials. Here, a breakdown of the most common types, plus some key features to look for.
- Swaddle-style sleep sacks: This design offers an easy-to-use alternative to classic swaddles, making them great for newborns. This type of wearable blanket constricts baby’s arms, which helps curb the moro reflex (also known as the startle reflex). However, as with regular swaddling, the use of sleep sacks that compress the arms, chest and body should stop once baby shows signs of starting to roll over.
- Sleeveless sleep sacks: Another good option is a sleeveless sack, which keeps baby’s feet and body safely tucked inside the sleeping bag, but leaves their arms free to move during the night. This type is safe to use from infancy through toddlerhood, as it provides babies with increased mobility, thanks to the armholes. Rather than the wrap-around style used for swaddle sacks, sleeveless wearable blankets are generally fastened with full-length zippers, which gives you easy access for diaper changes.
Now that you’ve got a grasp on the main types of wearable blanket, here are some key considerations to keep in mind.
- TOG rating: A TOG rating is a unit of measurement that determines the thermal insulation of a garment. Essentially, the higher the TOG rating, the warmer an item is. For babies and toddlers, you’ll typically find sleepwear with a rating of 0.5 to 3.5. When choosing a sleep sack, check the manufacturer’s guidelines and opt for a TOG rating to suit your particular climate and the temperature of your child’s bedroom. No matter the season, keep in mind: Babies shouldn’t be too bundled or too warm during sleep, advises Thistel.
- Size: “Be sure to look at the size of the sleep sack (including the age, height and weight details),” says Thistel. This way, you can ensure it will fit your child properly and create a safe, comfortable sleep environment for your little one.
- Material: When choosing a baby sleep sack, try to avoid styles made from synthetic materials. Natural fabrics—like cotton, muslin and wool—are breathable, warm and gentle on sensitive skin. All in all, it should be “lightweight, comfortable and breathable,” says Thistel.
- Zippers: Well-designed sleep sacks often feature dual zippers, meaning you can change baby’s diaper without having to remove the sleep sack entirely. If your child is slightly older—and prone to attempting daring escapes from the crib—an inverted zipper (or one that runs from top-to bottom) is a good option, as it’s harder for kids to unfasten.
Looking for some editor-approved options? Here are a few of our favorite, tried-and-true brands, plus online stores with a wide range of baby and toddler sleep sacks.
- Halo Sleep: Over 20 years ago, Halo Sleep created the first ever wearable blanket for babies—and the brand has been going strong since. Their innovative sleep sacks can be used from birth on, and are the number one choice of infant sleepwear in 1,600 hospitals nationwide. Choose from five different styles designed to suit every stage of development up to 5 years of age.
- Woolino: Woolino is well-loved by parents—and it’s easy to see why. The brand specializes in super-soft sleep sacks, made from a blend of organic cotton and Merino wool. These snuggly sleep sacks come in a variety of soothing colors and prints, and can be worn for sweet dreams year round.
- günamüna: Looking for ultra-cozy quilted sleep sacks? Then günamüna’s designs are sure to check all of the boxes on your list, and then some. The brand offers silky soft sleep bags, complete with duvet-like lining to keep your kiddo comfy and secure. You’ll love all the cute hues and prints available—plus, these wearable blankets come in infant and toddler sizes, so you can count on this brand for years to come.
- baby deedee: This mom-owned company specializes in designing sleep sacks, pajamas and cozy outerwear for babies and tots. baby deedee’s signature sleep bags come in three sizes for newborns, babies and toddlers with a range of fabrics to suit different climates. Plus, practical features such as a patented center zipper and shoulder snaps make them a dream to use.
Now that you’re familiar with the different types of sleep sacks available, check out a few of our favorite picks. From wearable blankets to sleeveless styles, here you’ll find the best baby sleep sacks for every age and stage.
Overall best baby sleep sack
Parents swear by baby sleep sacks from Halo Sleep—and it’s easy to see why. This classic sleeveless style nestles baby into a soft blanket, without the dangers of loose covers. It comes in three sizes, and the roomy design provides plenty of space for rambunctious baby kicks. Plus, it unzips down the front for quick and easy middle-of-the-night diaper changes. And when your little one inevitably has an accident, this sleep sack is machine-washable—phew!
Sizing: S (0-6 months) to L (12-18 months) | Material: 100% polyester | TOG rating: 1.5 TOG | Color options: 3
- Incredibly soft
- Recognized by the International Hip Dysplasia Institute (IHDI) to promote healthy hip development
- Some reports of broken zippers from reviewers
Best long-sleeve baby sleep sack
When frigid winter temperatures set in, make sure you have a cozy baby sleep sack on hand. This long-sleeve style from günamuna is essentially a duvet cover that your child can safely wear. It’s made from a rayon-bamboo blend, which is silky soft and quilted for added warmth. The 2.6 TOG fabric provides extra insulation for chilly nights, but it’s evenly distributed to ensure baby doesn’t get too hot. Plus, the asymmetric zipper runs from the top all the way along the base of the sack, so diaper changes will be a snap.
Sizing: 3-9 months to 24-36 months | Material: 95% bamboo viscose/5% spandex | TOG rating: 1.0 or 2.6 TOG | Color options: 9
- Super-soft, breathable bamboo fabric
- Quilted design for added warmth
- Four-way zipper offers easy access for diaper changes
- Air drying is suggested
Best bamboo sleep sack for babies
Searching for a temperature-regulating, wearable blanket for baby? You can’t go wrong with a bamboo sleep sack. The ultra-soft, breathable material will keep your little one cozy at an ideal temperature throughout the night. You’ll also appreciate the unique, J-shaped double zipper (complete with a zipper guard!) that will lend itself well to straightforward diaper changes, no matter the time of day. To meet your child’s needs and seasonal changes, this style is also available in a 0.5 and a 2.5 TOG rating.
Sizing: XS to XL | Material: 97% bamboo rayon/3% spandex (exterior), 100% polyester (filling) | TOG rating: 1.0 TOG | Color options: 49
- Buttery soft, breathable bamboo material helps regulate temperature
- Double zipper design for straightforward diaper changes
- Wide range of core, seasonal and limited edition colors and prints to choose from
- Colors may vary slightly in person
- Sleep sacks with printed designs may be slightly less soft than solid color styles
Best wool sleep sack for babies
For a baby sleep sack made of all-natural materials, there’s no better choice than the Woolino. Made from luxuriously soft Merino wool, this wearable blanket will regulate baby’s temperature all year round and comes in. It’s also 100 percent natural, machine-washable and has a dual-side zipper and opens completely flat so you can change baby without disturbing them too much. Plus, it comes with a nursery thermometer and a handy dressing guide so you can rest assured your little one is comfortable whatever the season. The only drawback is the relatively high price tag—but fans of the Woolino swear it’s easy to sell second-hand once your little one outgrows it.
Sizing: 0-6 months to 18-36 months | Material: 100% organic cotton (outer), 100% merino wool (lining) | TOG rating: N/A | Color options: 7
- Two-way zipper
- Suitable for all seasons
- Reviewers say it’s super durable
- High price point
- Color options aren’t available at all retailers
- No TOG rating
Best baby sleep sack for winter
When it comes to choosing the best baby sleep sacks for winter, this option from baby deedee sure fits the bill. It’s made from 100 percent polar fleece for high-quality coziness you can count on during the coldest months. Better yet, the wearable blanket has a cocoon-like shape and features shoulder snaps and an oversized zipper for your convenience and baby’s comfort.
Sizing: S (0-6 months) to L (18-36 months) | Material: 100% fleece | TOG rating: 1.2 TOG | Color options: 11
- Cozy, secure cocoon-like style
- Shoulder snaps and oversized front zipper for easy diaper changes and dressing
- Made from high-quality fleece to keep baby snug in cold weather
- Color options aren’t available at all retailers
- Parents say they wish the zipper was covered
Best cotton sleep sack for babies
Searching for an organic sleep sack for your little love? Enter: Burt’s Bees Baby Wearable Blanket, which is crafted from 100 percent GOTS-certified organic cotton. It’s available in a number of charming colors and patterns, and features a zipper that opens from the bottom (to make late-night changes quick and easy). It also has an interior zipper guard complete with a snappable cover. Another highlight: This buzzworthy organic sleep sack is an ideal choice for little ones with sensitive skin.
Sizing: S (0-6 months) to XL (18-24 months) | Material: 100% cotton | TOG rating: 0.5 or 1.5 TOG | Color options: 20
- Organic cotton material is ideal for babies with sensitive skin
- Zipper guard for baby’s comfort
- Available in plenty of patterns
- Some parents report that the zipper is stiff and difficult to fasten
Best sleeveless sleep sack for babies
If your little one can roll over independently, opt for a sleeveless sleep sack, like this one from ergoPouch. This transitional design features upper side snaps that can be closed or opened to create armholes, depending on baby’s mobility level. Other standout features you’ll love include the zip enclosure, the two-way zipper and gentle yet durable cotton-bamboo blend material. Better yet, this baby sleep sack is bell-shaped to promote proper hip and joint development, and has been approved by the IDHI. Pro tip: On extra-chilly evenings, layer baby up underneath this sleep sack for added warmth.
Sizing: 0-3 months to 6-12 months | Material: 55% organic cotton/40% bamboo viscose/5% spandex | TOG rating: 1.0 TOG | Color options: 9
- Transitional style can be used with or without armholes
- Approved by the IDHI to promote healthy hip development
- Two-way zipper for convenient diaper changes
- According to some reviewers, the neck is a bit too snug for their infants
Best fleece sleep sack for babies
When it comes to choosing a cozy, sleep sack for winter, you can’t go wrong with fleece. Case in point: This wearable blanket for babies from Halo Sleep. It’s made from super-soft micro-fleece that you and baby will love, and it has zipper covers to protect your infant’s delicate skin. What’s more, its extra-long length means you won’t have to size up as quickly—plus, it’s approved by the IHDI, so you can ensure it will foster healthy hip development.
Sizing: S (0-6 months) to XL (18-24 months) | Material: 100% polyester | TOG rating: 1.0 TOG | Color options: 20
- Extra-long design will meet baby’s changing needs
- Approved by the IDHI to promote healthy hip development
- Made from super-soft micro-fleece
- Turn inside out before washing
Best lightweight sleep sack for babies
You might know that aden + anais is the go-to brand for super-soft muslin swaddles and receiving blankets. Turns out, their baby sleep sack options are just as swoon-worthy. Made from a single layer of soft, breathable 100 percent cotton muslin, the open weave helps reduce the risk of overheating, offering just the right amount of comfort during summer nights and daytime naps. It can also be layered with warmer sleepwear for cooler temperatures and comes in a variety of adorable patterns. And like many of the best baby sleep sacks, this pick has a full-length zipper for easy changing access.
Sizing: 0-6 months to 18-36 months | Material: 100% cotton muslin | TOG rating: 1.0 TOG | Color options: 9
- High thread count for superior softness
- Versatile and breathable; can be worn year-round
- Machine-washable
- Parents report that the zippers aren’t great quality
Best quilted sleep sack for babies
Next up is a top-notch quilted sleep sack for babies. Made from 100 percent cotton muslin, the lightweight design is ideal for warmer months, and can be easily layered when it gets colder outside. When baby’s diaper needs to be changed, use the chin-to-toe zipper for easy access—then, count on the full-length enclosure to keep baby’s delicate skin safe. Choose from a number of adorable prints and colors, such as simple stripes, colorful dinosaurs and watercolor planets.
Sizing: S (0-6 months) to L (12-18 months) | Material: 100% cotton muslin | TOG rating: 1.1 TOG | Color options: 8
- Breathable, lightweight material is perfect for warmer weather
- Reviewers say they’re super-soft and wash well
- Color options aren’t available at all retailers
Best baby sleep sack with legs
This baby sleep sack with legs is aptly named “on the move”, thanks to its transitional, 2-in-1 design. During the day, it seamlessly converts into a walker bag so your kiddo can crawl, cruise and play to their heart’s content. Then, when nap- or bedtime rolls around, simply tuck away the feet to create a snug wearable blanket that’s perfect for snoozing in. The result? A cute, comfy sleep sack that your little one can wear all day (and night) long. It even features a travel-friendly seat belt slot, to keep your kiddo safe in their car seat or stroller as well.
Sizing: M (6-18 months) to L (18-36 months) | Material: 100% cotton | TOG rating: N/A | Color options: 15
- Adjustable 2-in-1 design grows with baby
- Features a travel-friendly seat belt slot
- Complete with adjustable snaps and covered zippers
- No TOG rating
Best transitional sleep sack for babies
Is your little one fed up with being swaddled? The Dream Sack gives baby the same cozy feeling that comes from Baby Merlin’s top-rated sleepsuit, with the freedom of movement to roll and kick as they get older. The roomy sack is made with a double layer of cotton to keep baby warm, safe and secure. Plus, a two-way zipper allows for easy diaper changes to make your job a little easier.
Sizing: S (6-12 months) to L (12-18 months) | Material: 100% cotton | TOG rating: 1.0 TOG | Color options: 3
- Double layer of soft cotton fabric
- Two-way zipper for easy access to baby’s diaper
- Runs large
- Some parents report it shrinks in the wash
We get it—creating a safe sleep environment for baby can be overwhelming at any stage. To streamline your search for the best sleep sacks, we browsed top-rated designs from leading baby brands and trusted online retailers. This way you can count on getting the best bang for your buck, while also having a dependable sleep sack that will meet your child’s needs.
When sourcing baby sleep sacks for our roundup, we considered several aspects, including (but not limited to) material, sizing options, long-sleeve and sleeveless styles, TOG rating, zippers, style and cost. We read user reviews to understand how these sleep sacks have worked for families, and didn’t consider anything with less than an average four-star rating. What’s more, to make sure we’re highlighting products that are safe and effective, we chatted with a pediatric sleep consultant and a pediatrician. This way, you’ll know what essential features and safety considerations to keep top of mind when you’re shopping. We also followed the safety recommendations of the AAP, and looked for approval from the IDHI, where applicable.
Interested in learning more about our editorial process? Read about how our team develops and reviews all articles here.
Plus, more from The Bump:
Jillian Thistel, is a certified pediatric sleep consultant in the Greater Toronto Area in Ontario, Canada. She is a member of the Association of Professional Sleep Consultants and founder of Twinkling Stars Pediatric Sleep Consulting
Loretta Cody, MD, is a board-certified pediatrician based out of Connecticut. She received her medical degree from New York Medical College and completed her residency at Yale New Haven Children's Hospital.
Healthy Children (AAP), Swaddling: Is it Safe for Your Baby?, July 2022
AAP, American Academy of Pediatrics Updates Safe Sleep Recommendations: Back is Best, June 2022
Learn how we keep our content accurate and up-to-date by reading our medical review and editorial process.
