How to Choose the Perfect Sleep Sack: A Guide for Parents

by Bailey Bouwman

Everyone loves a sleep sack - a relatively new baby product, they provide a safe alternative to blankets in the crib and toddler bed, while offering a good night sleep for your baby, toddler, and even big kids. Sleep sacks are one of our most popular baby shower gift purchases, as they can be expensive but worthy product to have on hand (plus, it's nice to have 2-3 sleep sacks)

What is a sleep sack

A sleep bag, also known as a sleep sack, is a wearable blanket designed for infants and toddlers. It serves as a safe and cozy alternative to traditional blankets in a crib or bed. The sleep bag is typically sleeveless and zips up around the baby, providing warmth and comfort while preventing the risks associated with loose bedding. This wearable blanket comes in various styles, including swaddle bags for newborns, regular sleep bags for infants, and sleep suits for active toddlers. The main purpose of a sleep bag is to ensure a secure sleep environment, keeping the baby warm without the need for additional coverings that could pose a suffocation risk.

As parents at Nest & Sprout, we understand the importance of a good night's sleep for both you and your little one. While, I don't remember the sleep sack being nearly as important 10 years ago with my first, they have definitely risen in popularity over the years. We spend much of our day helping parents like you find and choose the perfect sleep bag from our curated collection, or by making a recommendation to another brand or retailer who offers what they need. 

Let's take a look into the key considerations for finding the right sleep sack for you.

1. Understanding the Basics: Sleep Bag vs. Swaddle Sleep Bag vs Sleep Suit

Wearable blankets come in a few different styles with lots of different features and functions to adapt to the different needs at different ages and stages of life. Whether your navigating the startle reflex, or children who get up and go places - there's a wearable sleep choice for every kid.

  • Swaddle Sleep Bag: Ideal for newborns, swaddle sleep bags provide a snug wrap that mimics the womb, helping babies feel secure and preventing the startle reflex.
  • Regular Sleep Bags: Ideal for infants transitioning out of swaddles, offering freedom of movement and safety.
    • Common products include the Loulou Lollipop Sleep Bags, and variations form Nest Designs. 
  • Sleep Suits: Great for active toddlers, allowing them to move comfortably while staying cozy with their defined legs!
    • Nest Designs excels in this category with a variety of styles, wide size range.
​The question is - how does your child like to sleep? Do they need to be wrapped up in a cocoon, or arms out, and what about them legs for the older kids?

2. Temperature Regulation: TOG Rating

The other major consideration is the temperature rating. All Sleep sacks come with one that provides you with a standardized measurement for the product's performance.

  • Definition: TOG (Thermal Overall Grade) measures the thermal resistance of the sleep bag. The higher the TOG, the warmer the bag. Learn more about TOG.
  • Consideration: Choose the appropriate TOG based on the room temperature, ensuring your baby stays comfortably warm without the risk of overheating. TOG ratings are based on a naked diaper wearing child, additional clothing will make a bag warmer.
    • 1 TOG is a fantastic all year bag
    • 2.5 TOG is great for winter, cold rooms, and camping
    • 0.5 TOG is great for summer
TOG Rating
 Room Temperature Range


24°C (75°F) and above


21-23°C (70-74°F)


16-20°C (61-69°F)

Please note that these temperature ranges are provided as a general reference. Room temperature preferences may vary for individuals, and it's important to consider your child's comfort and adjust accordingly.

3. Perfect Fit: Choosing the Right Size

The best sizing tip is to measure the length  of your child. You'll want this length measurement when reviewing size charts, as it's more accurate than weight. 

  • Sizing: Opt for a sleep bag that fits well through your baby's chest, arms, and neck. While a longer sleep bag is acceptable, ensure it doesn't pose suffocation risks. One of the risks is the head coming through the arm hole
  • Longevity: Select a size that allows for extended wear, reducing the need for constant size upgrades. Lucky for you, most sleep bags offer a 3-12 month range in size. 

4. Feet Coverage: Sleep Bag vs. Sleep Bag Walker

For the older kids, you can choose between footed sleep suits or sleep bags. Bags can be great if you don't want your children to escape, but suits can offer that freedom of movement, and consistent warmth. 

  • Sleep Bag: Encloses the feet, suitable for babies who prefer covered feet.
  • Sleep Bag Walker: Features feet holes, allowing more freedom of movement. Ideal for toddlers transitioning to a bed.

This summers lightweight Sleep Suits from Nest Design offer that sleep feel and comfort, while providing warmth of a blanket. It can be a great choice for transitioning a child into a blanket, or or even a swaddle. 

5. Desirable Features: Customizing Your Choice

If you've made it this far and you're still trying to decide between two products, here's a few more things to consider.

  • Material: Consider the fabric, especially if your child has sensitive skin.
    • At Nest & Sprout we focus on skin friendly fabrics like organic cotton's, bamboo blends, and TENCEL. All of our sleep bags are designed with this skin sensitivity in mind and provide next level comfort
  • Zipper Placement: Front or dual-zipper options provide convenience for diaper changes. For some families, zipper is big influence on whether it goes up and down, to the side, and how the bottom opens.
    • You will find double zippers on most of our sleep bags
  • Print & Colours - choose the pretty one, or the print that has your heart whether it's fairies, gnomes, bears, or solids. 
  • Budget - sleep bags and suits made with premium materials, with transparent manufacturing have a different price point. You might consider a light weight bag with sleepwear. Lighter bags are lower cost, while sleepwear can be worn to get to the warmth you need.

6. Age-Appropriate Choices: From Newborns to Big Kids

  • Newborn to Six Months: Swaddle sleep bags or startle stop sleep bags.
  • Three to Six Months: Transition to regular sleep bags as babies outgrow swaddling.
  • Active Stage: Footed sleep bags for walking, climbing, and running.
  • Big Kid Status: Gradual transition to regular blankets.
    • Nest Designs Sleep Suits are available into a size 5/6 for your big toddlers, or your kids who just love the comfort of a sleep bag because of the weight, consistency, and more.

7. What to Wear Under the Sleep Bag: Considering Layers

  • General Rule: Dress your baby in one extra layer compared to what you find comfortable; and most  bags are rated for the temperature with just a diaper. It's why we see naked arms in a lot of sleep sack photos - or sometimes a bodysuit sneaking out from under.
  •  Onesies, footed PJs, or footless PJs can be worn under the sleep bag.

Embracing the Cozy Journey with Sleep Bags at Nest & Sprout

As you embark on the quest for the perfect sleep bag for your baby, toddler or even big kid, Nest & Sprout is here to accompany you every step of the way. Stop into our Prince George, BC children's boutique to view them in person, or explore the online listings for easy delivery across Canada.

Embrace the comfort, safety, and joy that sleep bags bring to bedtime, and may each night be filled with sweet dreams for your little ones and peaceful rest for you. Here's to cozy nights and the warm embrace of a well-chosen sleep bag! You got this. 

Leave a comment

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.