home of the ultimate baby sleep bag

perfect comfort for better and safer sleep
Woolino baby sleep bag - baby sleeping bag - merino wool 4 season ultimate baby sleep bag in Star White pattern

it's going to fit her even when she grows bigger (much bigger!)

saves you buying lots of sizes
Woolino baby sleep bag or sleepsack - baby sleeping bag - merino wool 4 season ultimate baby sleep bag in Gray stripes

it keeps him perfectly comfortable year-round

saves you buying different weight sleep bags
Woolino merino wool sleepwear

the superfine merino is so cozy against his skin

silky soft and hypoallergenic

Why Choose Woolino Sleep Sacks?

perfect comfort, year-round

Merino wool's natural climate control assists in regulating body temperature to keep baby warm when it's cold and cool when it's hot.

grows with baby

Universal size fits baby from 2m - 2yrs, saving you money. Simply close the underarm snaps to adjust the fit.

practical design

Shoulder snaps, two-way zipper, and seatbelt slots allow for easy dressing, changes, & transfers.

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4 Season® Ultimate Baby Sleep Bags

universal size: 2m-2yr

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4 Season® Ultimate Toddler Sleep Bags

universal size: 2-4yr

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4 Season® Basic Sleep Bags

standard sizing

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4 Season® Sleep Bags with Feet

standard sizing with cuffs

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Organic Cotton Sleep Bags

standard & universal size

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more sleep... for all

Our products are designed to make sure your baby is always safe and perfectly comfortable, which means a good night’s sleep for baby, but also for you.

And, we all know what a good night’s sleep means: a healthier, happier family!


merino wool

Merino wool is perfect for babies – for their safety and sleep quality. It’s naturally perfect!

Studies have shown that babies sleeping in merino settle more quickly, cry less, sleep longer, feed better, and even gain weight faster.

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BOGO 30% OFF organic cotton crib sheets



Can't say enough good things about the Woolino. It's a life changer. She instantly started sleeping through the night. The baby is nice and cozy in it, super soft and never scratchy, and just try to get her to sleep the night without it. You'll want two.

Dan Kon

Absolutely love this. Wish I could give 10 stars. The only sleep sack we use now, baby stays the perfect temp, not too hot or cold and the temperature varies here in New York during fall, winter and spring. Worth every penny.


Best Sleep Sack Ever! Woolino is by far my FAVORITE piece of baby gear. I wanted a bag that could handle the fluctuating temperatures of Ohio all while keeping my daughter comfortable. This is the ONLY bag you'll ever need. . . Plus the material is soft, light weight, made with quality workmanship, and is very easy to care for. My only regret is that I didn't purchase the Woolino sooner and wasted money on inferior infant bags of several different TOG & sizes.

K. Wrighton

...by far the best baby purchase we made. Cold out? No problem. Hot out? No problem. Won't leave home without it. Our 16 month old has been wearing it every night sInce about 5 months.

Danielle Hillon

How do I love thee, Woolino? 

Let me count the ways... I first purchased one out of desperation when my eczema coated son was so sensitive to polyester that all the warm PJs were making him scratch to bleeding. I bought the Woolino as a last resort. It is worth its weight in gold. It adjusts beautifully, stays on and keeps baby the perfect temp.

A. Hendrickson

Every child should have one. This is a must have!! Baby is comfortable – no need to worry about varying temperatures because the merino is for all climates (i.e.: keeps baby warm in winter and keeps baby cool in summer). It's wonderful!!... All other sleep sacks are miles behind this one.

Emma Son

Worth EVERY penny! Our 8 month old son, who had been having noticeable temperature drops in the night, despite extra layers of PJs, and who had been waking up 2-3 times a night his entire life began sleeping from 8:30pm - 7am upon introducing the Woolino! He calms down as soon as we put it on him and often times is not ready for us to take it off! HIGHLY recommend and very well worth the money!

Nancy L.

We LOOOOOOOVE our Woolinos. I am recommending them to all my friends – my only wish is that I had found then for my first daughter. I spent so much wasted time fretting over TOGs!!!

Verified Customer

Believe the hype. Game changer for my one year old sleeping through the night... I'd pay double for the magic this bag works.

Michael B. Jones

baby sleep sacks

Woolino baby sleep sacks are not only a safer alternative to loose blankets at bedtime - they also eliminate your worries about whether your child is cold or hot at night.  They're beautifully constructed with merino wool and organic cotton to keep your baby comfortable and cozy throughout the night and through all four seasons.

The elegant and intelligent design of our baby sleep sacks allows for easy dressing and simple night-time diaper changes.  The Woolino wearable blanket will help your child to get a good night of rest – which means you will too!