How do sleep sacks help babies sleep?

Sleep sacks keep babies warm while also allowing them to move their arms. “A sleep sack can help your baby sleep better as it allows the baby to feel the comfort and security of a swaddle [which helps] to continue the feel of the womb, but also keeps things safe with the baby's arms out and legs able to move around,” says McGinn. Plus, sleep sacks follow safe sleep guidelines: A sleep sack “acts as a wearable blanket, which adds another layer to prevent the baby from getting cold but keeps the crib safe with no loose bedding,” she says.

When do babies start wearing sleep sacks?

According to McGinn, “Sleep sacks can begin to be worn as early as 2 months of age.” Generally speaking, babies should be transitioned from swaddles to sleep sacks as soon as they start to show signs of being able to roll over since swaddles limit the use of their arms and may prohibit them from getting out of unsafe positions. When choosing a sleep sack, “Make sure the sleep sack fits well, and the baby can’t scoot down it and has their head covered,” says McGinn.

What is the difference between a sleep sack and a swaddle?

A swaddle is a large piece of cloth cut in the shape of a square that is folded and wrapped snugly around a newborn (kind of like a burrito) to soothe their startle reflex . A sleep sack is a loose-fitting wearable blanket that goes over the baby’s shoulders—keeping their arms free—and zips up to cover the feet and to ensure the blanket stays in place, so it does not pose a suffocation risk. Some sleep sacks, like the ErgoPouch Cocoon Wearable Blanket and Tommee Tippee Sleepee Snuggee , are designed to also serve as swaddles or as transitional blankets as the baby moves from a snug swaddle to a roomier sleep sack.

The 13 Best Sleep Sacks of 2023, Tested by Verywell Family

When your baby starts to show signs of rolling over from their back to their stomach, it’s time to transition them from a swaddle to a sleep sack. Also known as a wearable blanket, a sleep sack keeps your little one's body and legs secure and provides that same cocoon-like feel of a swaddle but gives them more freedom to move their arms and explore their space.

In our experience, sleep sacks belong on the “must-have” list of baby supplies for all new parents because they keep babies warm while also following the American Academy of Pediatrics' safe sleep guidelines, which advises against loose bedding near infants.

To keep your baby warm and comfy, look for a sleep sack in a material that's appropriate for the temperature in your baby's room and has the type of closure (snaps, zippers, or fabric fasteners) that is easiest for you to fumble with during a late-night diaper change. With these factors in mind, we talked to experts and conducted research to find the best sleep sacks for babies available on the market. We then put the top 20 sleep sacks to the test in the real world with the help of a team of 11 staff testers and their little ones, who used the sleep sacks in their homes, washed them several times, and evaluated their quality, durability, ease of use, value, and comfort. We also had a board-certified pediatrician from our Review Board review this article for medical accuracy and integrity surrounding sleep sacks, the safety of these products, and how to evaluate them.

What is the thermal overall grade (TOG) rating in sleep sacks?

The thermal overall grade indicates a garment’s thermal insulation. When it comes to sleep sacks, it basically tells you how warm they will keep your baby. The TOG range goes from 0.25 for thinner, lighter fabrics to 3.5 for warmer, more heavy-weight materials. In order to select the right TOG for your little one, consider the weather and season, the temperature in your baby’s room, additional clothing they’ll be wearing at night, and their overall sleep temperature (whether they tend to sleep warm or cool). Each of our product descriptions below indicates the TOG rating for the specific sleep sack.

Our Top Picks

Best Overall:

HALO Micro-fleece SleepSack Swaddle at Amazon

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Best Runner-Up:

Primary Muslin Sleep Sack at Primary.com

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Best Budget:

Simple Joys by Carter's Sleepbag at Amazon

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Best for Light Sleepers:

Baby Deedee Sleep Nest Lite Sleeping Bag Sack at Amazon

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Best for Diaper Changes:

Burt's Bees Baby Beekeeper Wearable Blanket at Amazon

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Best Transitional:

ergoPouch Cocoon at Amazon

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Best Transitional Runner-Up:

Tommee Tippee Baby Swaddle Wrap at Amazon

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Best Prints:

Copper Pearl Sleep Bag at Amazon

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Best Fleece:

HALO Sleepsack Blanket at Amazon

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Best for Cold Weather:

Baby Deedee Sleep Nest Sleeping Sack at Amazon

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In This Article

Our Picks
How We Tested
What to Look For
FAQ
Why Trust Verywell Family

Amazon

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Our Ratings

Comfort

4.8/5
Ease of Use

5/5
Durability

5/5
Value

5/5

Pros

Functions as a swaddle and sleep sack
Handy instructions are located inside the swaddle flap
Maintains high quality after multiple washes

Cons

Limited size options

The Halo Sleep Sack Swaddle pulls double duty: It’s a cozy swaddle for infants, then it helps you transition your baby’s arms out of the sack when they start to roll. A silky instruction diagram is conveniently placed on the inside flap of the swaddle wing for you to refer to (and it won’t irritate the baby). To swaddle, simply wrap the wings around the baby and use the hook and loop closures to secure them. When your baby becomes more mobile and shows signs of rolling over, transition them to a sleep sack, taking one arm out of the swaddle at a time.

Made from plush 100% polyester microfleece, this sleep sack is warm and cozy, but it’s also designed to wick away moisture, so your baby doesn’t overheat. Plus, there are no tags, metal, or anything that would irritate the baby. In our test, it also held up well in the wash and didn’t pill or get rough.

We’re impressed by the value of the Halo Sleep Sack Swaddle; for $30, you get a swaddle and a sleep sack that will help you transition your little one between the two. There are several colors and patterns to choose from, though sizing only goes up to roughly 6 months old, or 18 pounds.

Price at time of publication: $30

^{Key Specs:
Material: Polyester microfleece | Age Range: 0 to 6 months old | Machine Washable: Yes | TOG: 3.0}

Primary

View On Primary.com

Our Ratings

Comfort

5/5
Ease of Use

5/5
Durability

5/5
Value

5/5

Pros

Bright colors
Lightweight cotton
Safety tab around zipper

Cons

Fabric is thin

The Primary Muslin Sleep Sack is a high-quality sleep sack that comes in vibrant colors and patterns little ones (and their parents) are sure to love. We appreciated how lightweight the 100 percent cotton material is, which makes it great for summer and very soft against the skin. We did find the fabric to be a bit thin—if we were to compare it to adult blankets, we'd say it is more like a top sheet than a quilt, so it’s best suited for warmer weather.

The zipper, which is covered in a layer of fabric, so it doesn’t irritate or poke the baby’s skin, zips from the bottom to the neck. Note that this sleep sack runs a bit small, so you may want to size up if your kiddo is in between sizes, especially because it doesn’t shrink in the wash. Luckily, there are four size options to choose from.

Though this is a high-quality item, the Primary Muslin Sleep Sack is priced similarly to other picks on our list, earning it our Best Runner-Up spot. In addition to the rainbow striped option, it’s available in a rainbow hearts pattern. (Both patterns can be opportunities to start teaching your toddler the colors of the rainbow.)

Price at time of publication: $35

^{Key Specs:
Material: 100% cotton muslin | Age Range: 0 months old to 2 years old | Machine Washable: Not listed | TOG: Not listed}

4.2

Amazon

View On Amazon

Our Ratings

Comfort

3/5
Ease of Use

5/5
Durability

5/5
Value

3.8/5

Pros

Affordable three-pack
Available in multiple sizes
Lightweight material

Cons

May not be warm enough for colder months

If you’re looking to stock your baby’s closet on a budget, this three-pack from Carter’s is lightweight, convenient, and affordable. The multi-pack, which is available in three sizes, comes with 100% polyester sleep sacks in different patterns. At under $30 for a pack of three, the Simple Joys by Carter’s sleep sacks particularly impressed us when it comes to value. We also liked the fabric safety tab, which snaps around the zipper to keep it away from the baby’s face. Plus, the snaps and zipper are straightforward, and the zipper is pretty smooth and doesn't catch.

During our test, these sleep sacks held up well in the wash, maintaining their shape and actually getting a bit softer after a few washes. And another benefit of buying a multipack is that you always have backups when one’s in the laundry. Parents of wiggly little ones will also appreciate the armholes, which are big enough to make it easy to put on a wiggly baby but still stay snug. Keep in mind that these sleep sacks are lightweight, so they’re ideal for spring and summer or babies that tend to run hot.

Price at time of publication: $27 (Pack of 3)

^{Key Specs:
Material: 100% polyester | Age Range: 0 to 9 months old | Machine Washable: Yes | TOG: Not listed}

4.9

View On Amazon View On Albeebaby.com View On Target

Our Ratings

Comfort

5/5
Ease of Use

5/5
Durability

5/5
Value

4.6/5

Pros

Toddler sizes available
Quiet zipper and snaps

Cons

Not designed for colder weather

If your kiddo is a light sleeper, the Baby Deedee Nest Lite Sleeping Sack is a helpful solution. The large-toothed zipper and metal shoulder snaps are quiet and easy to use, which helps get the wearable blanket on a sleeping baby without waking them up.

This sleep sack comes in a wide variety of sizes—from newborn up to 3 years old—and is available in several color combinations. Made from breathable 100 percent cotton, we found the material to be super soft and cushiony, like a comforter. The zipper zips from the top down to facilitate diaper changes, and it did well in the wash.

Price at time of publication: $39

^{Key Specs:
Material: 100% cotton | Age Range: 0 months old to 3 years old | Machine Washable: Yes | TOG: 0.6}

4.3

Amazon

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Our Ratings

Comfort

5/5
Ease of Use

2/5
Durability

5/5
Value

5/5

Pros

Zips from the top down
Extra long
100% organic cotton is great for sensitive skin

Cons

Zipper style might not be the best for toddlers

Middle-of-the-night diaper changes are tough enough as it is, so you don’t want a tricky zipper getting in the way. This sleep sack from Burt’s Bees Baby zips from the top down, so it’s easy to change your kiddo’s diaper without needing to take the whole sleep sack off. It also has an interior zipper guard and a zipper cover to keep the baby safe.

We appreciate that the sleep sack is extra long to allow little legs and hips to move freely, which can help avoid the risk of hip dysplasia, according to sleep expert Alanna McGinn. Plus, the 100 percent organic cotton material is easy on sensitive skin and is GOTS-certified, meaning it meets high standards of sustainability. We found that it washed well and didn’t shrink or stretch in the wash.

While the zipper design is great for babies’ diaper changes, it isn’t as ideal for toddlers, as it could be tricky to get the sleep sack onto a squirmy little one. At $33, this sleep sack is reasonably priced and does what parents need it to do: keep babies and toddlers cozy and secure at night.

Price at time of publication: $33

^{Key Specs:
Material: 100% cotton | Age Range: 0 to 18 months old | Machine Washable: Yes | TOG: 0.5}

4.9

Amazon

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Our Ratings

Comfort

5/5
Ease of Use

5/5
Durability

5/5
Value

4.6/5

Pros

Available in solids and patterns
Designed for the transition from a swaddle to a sleep sack
Snaps on arm holes are easy to use

Cons

Might not be tight enough when used as a swaddle

When babies start becoming mobile and show signs of being able to roll over, it’s time to transition them from a swaddle to a sleep sack. Made from organic cotton, this sleep sack from ergoPouch helps bridge that gap. We put this feature to the test with the assistance of a 6-month-old baby, first using it as a traditional swaddle with her arms inside, then leaving one arm out for a few days before she was ready to sleep with both arms out.

The snug yet stretchy sack allows babies to move around but still has a tighter fit, almost like a hug. To make getting your little one into the sleep sack easier, the shoulders have convenient snaps. Plus, the fabric did not get rough or pill after being washed.

Overall, this sleep sack allows for plenty of mobility when little ones are starting to move more. In addition to the 0.2 TOG version we tested, the sleep sack is available in 1.0 TOG and a heavier 2.5 TOG version.

Price at time of publication: $30

^{Key Specs:
Material: Organic cotton | Age Range: 0 months old to 1 year old | Machine Washable: Yes | TOG: 0.2}

4.5

Target

View On Amazon

Our Ratings

Comfort

5/5
Ease of Use

5/5
Durability

4/5
Value

4/5

Pros

Two-way zipper
Arms can go in or out based on the baby’s abilities

Cons

Limited color options

Another great option for transitioning your baby from a swaddle to a sleep sack is this wrap from Tommee Tippee. The diagonal zipper allows you to transition your little one from both arms in, to one arm out, to both arms out, and since the zipper goes two ways, late-night diaper changes are made easy.

The 1.0 TOG sleep sack is available in two sizes—newborn to 4 months old and 3 months to 9 months old—and comes in a few colors. It’s designed to fit snugly on top and looser on the bottom, so the baby’s hips are free to move, earning it approval from the International Hip Dysplasia Institute. We also appreciate the covered zipper and the soft cotton fabric that’s smooth on the baby’s skin.

Price at time of publication: $26

^{Key Specs:
Material: Cotton | Age Range: 0 to 9 months old | Machine Washable: Yes | TOG: 1.0}

4.9

Amazon

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Our Ratings

Comfort

5/5
Ease of Use

5/5
Durability

5/5
Value

4.5/5

Pros

Zips from the bottom for easy diaper changes
Available in lots of adorable patterns
Three-layer construction

Cons

Zipper may be difficult to maneuver

For a sleep sack that is as adorable as it is functional, consider the Copper Pearl Sleep Bag. Available in over 100 colors and patterns on the brand’s website, this sleep sack is constructed from three layers of soft yet stretchy fabric and is available in two sizes.

The care instructions are located on the outside of the back of the sleep sack, so parents don’t need to dig around when doing laundry—plus, there’s no care tag inside to bother the little one’s skin. The sleep sack also stood up to the wash, feeling just as soft after washing as it was brand new—maybe even softer.

We like that the zipper unzips from the bottom, making it easier to change the baby’s diaper without causing a chill or waking them more fully. Plus, it doesn’t catch on any fabric on the way down or up. While this sleep sack is a bit pricier than some other options, we think it’s worth it for the cute prints and luxurious feel.

Price at time of publication: $45

^{Key Specs:
Material: Polyester and rayon blend | Age Range: 0 months old to 1 year old | Machine Washable: Yes | TOG: 1.25}

4.8

Amazon

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Our Ratings

Comfort

4.5/5
Ease of Use

5/5
Durability

5/5
Value

4.5/5

Pros

Soft microfleece material
Zips from the top

Cons

Gets less plush after several months of use

A microfleece sleep sack helps keep your baby warm and cozy while they snooze. This version from Halo is made from a super soft microfleece fabric that’s not overly hot and comes in a wide variety of colors and patterns.

This sleep sack has a zipper that zips from the top down, which not only makes diaper changes easier but also makes it trickier for toddlers to unzip themselves. We appreciate that the fabric does not stick to regular cotton sheets, giving the baby a full range of motion. (This also makes it easier for parents to take their baby out of the crib.) The sleep sack comes in several sizes—small, medium, large, and extra large—so you can size up as your little one grows while keeping the feel of their sleep sack consistent.

At $30, this soft, cozy sleep sack is priced competitively with several of our other top picks. We recommend it if you’re looking for a fleece option or your baby tends to run cool.

Price at time of publication: $30

^{Key Specs:
Material: 100% polyester micro-fleece | Age Range: 0 months old to 2 years old | Machine Washable: Yes | TOG: 1.0}

Amazon

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Pros

Warm and cozy
Available in toddler sizes
Snaps and zipper are quiet

Cons

Not available in patterns
Not suited for warmer months

If you live in a cooler climate or are searching for a sleep sack for your winter baby, check out the Baby Deedee Sleep Nest Sleeping Sack, which is essentially a sleeping bag for your little one. Featuring a duvet-like 100% cotton shell and 100 percent polyester filling, this 2.5 TOG sleep sack will keep your baby extra warm in the cold. The material behind the zipper is extra thick, so it never comes into contact with the baby’s skin, and the snaps on the shoulders make it easy to get your little one’s arms into the sack. This sleep sack is wider at the bottom, giving your baby enough space to stretch their legs and explore different sleeping positions.

We washed this sleep sack quite a few times during our test, and it came out like new every time, always soft and with no visible pilling. Though it’s a bit pricier than some other options, you’re paying for high-quality, thick material that will keep your kiddo warm, even when it’s chilly out. It’s available in multiple solid colors.

Price at time of publication: $42

^{Key Specs:
Material: Cotton and polyester | Age Range: 0 months old to 3 years old | Machine Washable: Yes | TOG: 2.5}

4.8

Amazon

View On Amazon View On Gunamuna.com View On Maisonette.com

Our Ratings

Comfort

5/5
Ease of Use

5/5
Durability

5/5
Value

4/5

Pros

Zips all the way around
Handy shoulder snaps
Soft bamboo material

Cons

Threads may occasionally come loose

Bamboo fabric is known for being silky smooth and soft, and this Gunamuna Sleep Bag Duvet delivers on that promise. It also performed marvelously during our test. The fit was great for babies—not too tight around the neck or arms, and with ample room to move the legs. The bamboo fabric felt soft like a cloud after several washes, and the high-quality material held up well, with no noticeable pilling or roughness.

One of the key things to look for when buying a sleep sack is if it’s easy to put on a wiggly baby. This sleep slack has a zipper that goes around both sides, giving caregivers the option to unzip just the bottom for a diaper change, keeping the baby warm. There are also handy snaps on one shoulder to help secure the little one’s arms correctly.

We all want to keep our babies safe, which is why we appreciate that this sleep sack meets the Oeko-Tex Standard 100 certification, meaning it’s free from hundreds of harmful substances and toxic chemicals. The filling is also hypoallergenic, making it great for kiddos with allergies or sensitive skin. There’s also a heavier version available for cooler weather.

While this sleep sack is pricier than other options, we think the splurge is worth it for the ultra-soft bamboo fabric, high-quality stitching, and adorable patterns.

Price at time of publication: $52

^{Key Specs:
Material: Bamboo viscose and spandex | Age Range: 3 months old to 3 years old | Machine Washable: Yes | TOG: 1.0}

4.8

Bloomindale's

View On Nordstrom View On Bloomingdales View On Littlegiraffe.com

Our Ratings

Comfort

5/5
Ease of Use

3.5/5
Durability

5/5
Value

4.5/5

Pros

Cozy chenille fabric
Material didn’t get matted in the wash

Cons

Snaps may be difficult to open

If you’re looking to splurge on a baby gift, this cozy chenille sleep sack from Little Giraffe is an adorable present for parents-to-be. Available in a few pastel and neutral colors, it would make a sweet addition to any nursery. During our testing, the chenille fabric maintained its softness in the wash and didn’t become matted, impressing us with its durability.

The sleep sack is secured with a zipper and four snaps on the chest. While the snaps may be a little tough to open and close, there’s no need to worry about the zipper poking your baby since it only goes halfway up. Overall, we found the quality of the fabric and closures to be sturdy and well-made.

One of our favorite touches is that some retailers ship this sleep sack in adorable packaging that would be great for gifting. While it is an investment, it’s sure to wow at the next baby shower you attend.

Price at time of publication: $63

^{Key Specs:
Material: 100% polyester | Age Range: 0 to 6 months old | Machine Washable: Yes | TOG: Not listed}

Amazon

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Pros

Budget-friendly two-pack
Long sleeves keep arms warm

Cons

May need to size up to fit pajamas underneath

Score two long-sleeve sleep sacks for less than most of the options on our list, thanks to Hudson Baby’s affordable pricing. They’re made from 100 percent cotton that’s soft, stretchy, and non-irritating. Comfortable and lightweight, the fabric's stretchiness made it easy to put on and off babies during our test, including a wiggly 15-month-old.

These sleep sacks come in several color and pattern combinations, including animals, flowers, and footballs. The zipper zips from the bottom to the chin and is protected by a layer of fabric, so it doesn’t hurt delicate skin. The sleep sack seemed to fit a bit snugly on toddlers, so consider sizing up if your little one wears thicker pajamas.

Price at time of publication: $13

^{Key Specs:
Material: 100% cotton | Age Range: 0 months old to 2 years old | Machine Washable: Yes}

How We Rated the Sleep Sacks

4.8 to 5 stars: These are the best sleep sacks we tested. We recommend them without reservation.

4.5 to 4.7 stars: These sleep sacks are excellent—they might have minor flaws, but we still recommend them.

4.0 to 4.5 stars: We think these are great sleep sacks, but others are better.

3.5 to 3.9 stars: These sleep sacks are just average.

3.4 and below: We don't recommend sleep sacks with this rating; you won't find any on our list.

How We Tested the Best Sleep Sacks

Eleven of our staff members tested nearly 20 sleep sacks in their own homes, putting their babies and toddlers to bed in the sleep sacks every night. At the end of the test, they assessed their child’s sleep quality in addition to the sleep sack’s comfort, ease of use, durability, and value. We also spoke with sleep consultant Aubrie DeBear, PsyD, and Alanna McGinn, CEO and sleep expert of Good Night Sleep Site, for additional insights into picking the best sleep sacks for little ones.

Our testers were instructed to unpack the sleep sacks, wash them as indicated by the manufacturer, and inspect them for any loose pieces or hanging threads. Next, they timed themselves as they placed their child correctly in the sleep sack, noting how easy it was, if the baby felt cool enough, if arms and legs fit in well, and if the closures worked properly. Testers then put their child to sleep in the sleep sack every night, washing it as instructed when necessary. They observed whether there were any changes to the quality of the sleep sack, including if it shrunk or faded, if zippers became loose, or if the fabric pilled. Additionally, they noted how diaper changes went and whether their child’s sleeping patterns changed over the course of the testing period.

What to Look for in a Sleep Sack

Safety

To keep your baby safe, check that a sleep sack fits them correctly, making sure to review its age and weight ranges before you make your purchase. Unlike a swaddle, a sleep sack allows babies to move their arms around, which is crucial for babies that are starting to roll onto their stomachs and become more mobile. In order to create a safe sleeping environment and reduce the risk of SIDS, parents should follow the Safe Sleep Guidelines from the AAP. Babies should sleep in their own crib with a firm mattress free of soft objects and loose bedding like blankets, pillows, toys, or anything else that could cause suffocation.

Additionally, it is important to note that the AAP and McGinn strictly advise against the use of weighted sleep sacks or blankets for babies “as they can be too heavy on the baby's chest and lungs.” DeBear also notes that parents should make sure the sleep sack has a high-quality zipper because it could pose a suffocation risk if it comes undone during the night.

Design

There are several different sleep sack designs to choose from based on your child’s age, size, and mobility. Keep your child’s abilities in mind when choosing between the various kinds, which include a swaddle sleep sack that keeps babies' arms wrapped tightly, a transitional sleep sack that can go from swaddle to sack as babies grow (like the ErgoPouch Cocoon Wearable Blanket), a standard sleep sack that covers the body while keeping arms free (like the Little Giraffe Stretch Chenille Dreamsack), or an early walker sleep sack that lets babies' feet poke out of the bottom.

Materials

Sleep sacks come in a variety of materials. They include light and breezy cotton muslin, eco-friendly bamboo rayon and organic cotton, polyester blends that can be easier to care for, and extra warm polyester microfleece.

You’ll find that most sleep sacks feature a Thermal Overall Grade (TOG) value, which indicates the level of warmth they provide the baby. “The higher the TOG value, the warmer the sleep sack,” McGinn tells us, adding, “An ideal [nursery] temperature is between 69 to 72 degrees, and we always want to promote a cooler sleep environment for baby.” Higher TOG options on our list include the Baby Deedee Sleep Nest Sleeping Sack and Halo Sleep Sack Swaddle, while the ErgoPouch Cocoon Wearable Blanket and Burt's Bees Baby Beekeeper Wearable Blanket are lighter options.

You don’t want to purchase a high TOG microfleece sleep sack in the middle of the summer, and you may want to avoid a sleep sack that isn’t safe for the washer or dryer if you're not up for hand-washing, so look closely at how the product is made before purchasing. DeBear also suggests considering the climate you live in and the temperature you generally keep your home at to help you decide which material is best for your child.

Frequently Asked Questions

How do sleep sacks help babies sleep?

Sleep sacks keep babies warm while also allowing them to move their arms. “A sleep sack can help your baby sleep better as it allows the baby to feel the comfort and security of a swaddle [which helps] to continue the feel of the womb, but also keeps things safe with the baby's arms out and legs able to move around,” says McGinn. Plus, sleep sacks follow safe sleep guidelines: A sleep sack “acts as a wearable blanket, which adds another layer to prevent the baby from getting cold but keeps the crib safe with no loose bedding,” she says.
When do babies start wearing sleep sacks?

According to McGinn, “Sleep sacks can begin to be worn as early as 2 months of age.” Generally speaking, babies should be transitioned from swaddles to sleep sacks as soon as they start to show signs of being able to roll over since swaddles limit the use of their arms and may prohibit them from getting out of unsafe positions.
When choosing a sleep sack, “Make sure the sleep sack fits well, and the baby can’t scoot down it and has their head covered,” says McGinn.
What is the difference between a sleep sack and a swaddle?

A swaddle is a large piece of cloth cut in the shape of a square that is folded and wrapped snugly around a newborn (kind of like a burrito) to soothe their startle reflex. A sleep sack is a loose-fitting wearable blanket that goes over the baby’s shoulders—keeping their arms free—and zips up to cover the feet and to ensure the blanket stays in place, so it does not pose a suffocation risk.
Some sleep sacks, like the ErgoPouch Cocoon Wearable Blanket and Tommee Tippee Sleepee Snuggee, are designed to also serve as swaddles or as transitional blankets as the baby moves from a snug swaddle to a roomier sleep sack.

Why Trust Verywell Family

Phoebe Sklansky is Verywell Family’s Associate Commerce Editor. As a commerce writer and avid shopper herself, she enjoys helping readers find the best products for their unique needs.

Ashley Ziegler is a full-time parenting writer and mom to a 2-year-old and a 4-year-old. She has personal experience in researching and purchasing a variety of children’s products, including sleep sacks. Key considerations she used when selecting these recommendations include expert advice, age appropriateness, and user reviews.