4 Season Ultimate Baby Sleep Bag
$
109.00
Free shipping & returns for Babylist orders $45+
color
Night Sky
size
0-2 Years
1
Overview
Description
Sleep bags fit around your baby as an alternative to a blanket, creating a snug enclosure that still has room for arms and legs to move freely. And with a bag, there’s no chance that a blanket can cover your baby’s face.
Parents love this one for a few reasons—a big reason is that it keeps baby at the just-right temperature in all seasons thanks to the extra breathable Merino wool lining. High-quality merino wool naturally regulates temperature to help keep little bodies warm when it’s cool and cool when it’s warm. The outer layer is made with soft GOTS certified organic cotton.
The sleep bag is ideal for room temperatures 63-77 degrees. For a helpful bonus, it comes with a nursery thermometer and dressing guide so you know what to put baby in under the sleeping bag (i.e. layers; something sleeveless, etc.).
The Ultimate features double shoulder snaps and a two-way side zipper, so it opens up completely flat for easy dressing without waking baby. For easy nighttime diaper changes, you can open the bottom zipper only. Zipper-pull guards to protect baby’s skin.
The Ultimate Sleep Bag has universal sizing, so one bag can work from two months to two years. Parents love this.
For peace of mind, this sleep bag meets child safety requirements and all the fabrics and accessories are OEKO-Tex 100 certified (tested for 100 harmful substances). It’s also machine washable, but merino wool by nature is self-cleaning and doesn’t need to be washed as often as other fabrics.
What we about it
This silky-soft and hypoallergenic merino wool inner layer keeps baby comfy in all seasons. Also, one size works from two months to two years.
Details
- Made with 100% Australian merino wool lining; organic cotton outer
- Universal sizing: 2 months to 2 years
- Breathable and hypoallergenic
- Two-way zippers
- Machine washable
More to consider
Q&A
Have a question? Ask an expert.
Start typing and see existing answers.
What TOG is this?
Best Answer: The Woolino 4 Season Ultimate Baby Sleep Bag is rated at 1.0 tog, making it a breathable option designed for year‐round use.
What's the maximum height (length) for this sleep sack?
Best Answer: This universal sleep sack is intended for little ones that are between 23 to 35 inches in length, and 10 to 32 pounds.
What is the youngest you can use this sleep sack?
The Woolino sleeping blanket says in the description that it is for between two months and 2 years and I have a brand new grandbaby that's about six and a half pounds and it's very cold will it fit him now?
Customer reviews
310 Ratings
1-10 of 310 Reviews
The gray striped one is more of a green color
Oct 9, 2025
Best sleep sack ever!!!!! Keeps my son warm/cool whenever needed and he loves it too. So snuggly and soft- will definitely be buying more!!
Sep 15, 2025
Great quality sleep sack! Soft and holds up somewhat well to washing.
Sep 11, 2025
The sleep sacks are perfect all year round which is huge! It’s soft and comfy and can be used from baby to toddler! We have two woolinos and love them!!
Aug 31, 2025
I gave this as a gift to my son and their first baby. They are excited to try it out when the baby is bigger. A friend of mine recommended it to me. She LOVES hers.
Aug 25, 2025
Perfect, soft and warm, baby sleep well in it. Bought a second one after a few months with the 1st 😁
Aug 25, 2025
I bought this for my daughter's new baby boy. My son and daughter-in-law had 1 they used for their two girls and it kept them cozy and warm all year long.
Aug 17, 2025
Very soft and spacious. Love it so far!
Aug 16, 2025
It's such high quality and so soft. I'm so glad my son will be able to wear it for at least a year and a half!
Aug 14, 2025
Wish I heard about woolino and tried them sooner. This sack keeps my boy cool even when his room is warmer in the summer evenings. His legs don’t get cold with the AC and fan running in the evening like he did with the popular bamboo sleep sacks. It’s hard to know what temp the room will be with hot summer days and AC but this sack gives me peace knowing it will regulate his temp.
Jul 28, 2025
