Choosing The Best Summer Sleeping Bag

baby sleeping in their cot wearing a woolbabe sleeping bag

Summer Sleeping Bag Guide

We recommend using a sleeping bag year round, including during the hot days and nights of summer.

Sleeping bags used without any additional bedding help ensure your baby or toddler is sleeping safely and stay a comfortable temperature all night.

Sleeping bags are also a very strong sleep association, reminding your child that it's sleep time no matter where they are. This is very useful when you are on holiday or wanting your child to sleep when you are out and about over the summer.

Size, fabric type, tog rating, warmth & sleepwear combinations, zip position and more are covered and linked to from this page about infant sleep bags.

Use the links below to jump to each section and find the sleep sack that is the best choice for your baby. Learn how to dress your baby to the room temperature with their sleeping bag, understand about tog ratings to keep and hot to avoid overheating. 


Our Summer Sleep Sack Collection

We only stock brands we really rate as being good quality and value for money. Plus we make sure all our sleeping bags meet the relevant safety standards.

Having said that, we do have some particular favourites and also some clear best-sellers with our customers.

  • Woolbabe 3-seasons bag - These Cover the widest temperature range, can be used for most of the year.

  • Woolbabe summer bag - A single layer of breathable Merino & Organic cotton blend. Stay comfy even if sweaty and are a generous length.

  • ErgoPouch 0.2 & 0.3 tog - A lovely light and cool option, available in either the regular sheeting or jersey (0.3 tog) organic cotton.

  • The Sleep Store 0.5 & 1.0 tog - Beautiful GOTS certified organic cotton in a range of prints desigined by us and finished with high quality fastenings. Excellent value.

  • Grobags by The Gro Company - 0.5 tog & 1.0 tog - grobag is an incredibly popular brand due to their excellent quality. The 0.5 tog is one of our coolest options and the 1.0 tog is ideal for most locations in summer and can be use for day sleeps in cooler months.

  • Aden+Anais muslin bags - one of our best value and most popular bags for summer, made from cool muslin. Just note the size range is 0-6, 6-12, 12-18 or 12-24 months so you need to buy these more often to have the right size.

  • Nuzzlin by Love To Dream - Made from a stretchy muslin-like cotton

  • Slumbersac 0.5 & 1.0 tog - excellent value range of sleeping bags if you are on a budget or need a lower priced second bag.



Tog Ratings & Warmth Guides For Sleeping Bags

baby in sleeping bag and bodysuit happy to see mum

Many sleeping bags use the European TOG rating system to indicate how warm the sleeping bag is and what season they are suitable for. The higher the TOG, the warmer the sleeping bag. 

Summer sleeping bags are usually 1.0 or under, depending on where you are and the tempearture range in your child's bedroom. In some parts of New Zealand, a 2.5 tog or winter weight bag will still be needed overnight.

A number of external factors determine the tog rating of the sleeping bag that should be used. These include the quantity of clothing the baby is wearing, the temperature of the infant’s bedroom, the baby’s health and the amount of bedding necessary to keep an individual infant warm – this may vary as it does for adults.  

Many sleeping bags that we stock come with a free nursery thermometer to help you select which tog baby sleeping bag to use and what sleepwear to put your baby in. 


A tog is roughly equivelant to a layer of clothing or a light blanket. Many of our sleeping bags are available in three tog ratings. In the warmest months of the year a 0.5 tog or lower is recommended. Inbetween seasons a 1.0 tog rated bag is usually suitable. When room temperatures can vary between 16-20 degrees a 2.5 tog rated bag is a good solution. It's important to keep baby cool and avoid overheating, after all they can't simply throw off their sleeping bag if they get too hot. We always recommend natural breathable fibres for clothing and pyjamas, and inparticular merino can help with temperature regulation.

Are 0.2 tog rated bags much cooler than 0.5 tog rated bags? We don't think there is a noticable difference between these two ratings, particularly when comparing tog rating across brands. It's always important to check your baby regularly to ensure they do not overheat.

Scroll down to the table below to find a dressing guide for our most popular styles or click here to see the Woolbabe clothing guide.


Why are some sleeping bags tog rated and others are not?

Sleeping bags with polyester or from fibres that can be consistently perform to a testing standard or set temperature range tend to be tog rated. In general sleeping bags made with Merino are not tog rated, as they are natural fibre which adjusts according to temperature, this is one of the reasons natural fibre Merino sleeping bags are so popular. Merino is also amazing a wicking moisture away from the skin. Woolbabe bags have the widest temperature range - the 3-seasons bag can be used for rooms 18-28 degrees, duvet weight bag can be used 14 to 22 degrees.

To read more about which Woolbabe to choose for the room temperature and the clothing guide click here.

Sleeping bags and sleep sacks at The Sleep Store

Which sleeping bag option can be used in spring and autumn as well as summer?

The Woolbabe 3-Seasons is the best option for use through these times of year. As the seasons change you'll need to adapt your baby's clothing that you combine with the Woolbabe 3-seasons to keep them comfortable at the room temperature they are using at. If the room temperature is consistently high then we recommend investing in a dedicated summer weight sleeping bag. See the dessing guide below for further details

What to dress baby in at night

The warmth of the bag will vary enormously with what clothing you use inside the bag. You can easily add another layer of clothing to make the bag warmer, such as using an extra merino bodysuit. 

Using a room thermometer (eg gro egg) to accurately determine the temperature in your child's room is a good idea and will be a big help, particularly when it comes to choosing the clothing and sleeping bag combination for the temperature.

Many sleeping bags now come with a clothing guide in addition to a free room thermometer to help you decide which clothing combination to use. Use your common sense too, the clothing guides are just a starting point and you will still need to monitor your child and adjust their clothing and sleeping bag combination so that they are a comfortable temperature and don't overheat. Watch the videos above for further tips and advice. 

Scroll down to the table below to find a dressing guide for our most popular styles or click here to see the Woolbabe clothing guide.

Sleeping Bag & clothing guide

The guide below will help you to choose a sleeping bag that is suitable for the temperature of the room which baby will be sleeping in. Babies warmth needs vary for child to child just as they do for adults so use as a guide and adjust to suit your baby accordingley. Check your baby regularly to ensure they do not overheat or are waking up from being too cold. The optimal room temperature is around 18 degress celcius.  By adjusting the clothing that baby wears inside the sleeping bag you'll help to make baby more comfortable at different room temperatures. Try to keep baby's room temperature below 27 degrees so that they don't overheat. If the room temperature drops and baby is waking up from the cold choose a warmer weight sleeping bag. Sleeping bags like the Woolbabe are fantastic at adjusting to a wider range of room temperatures because of the use of naturally temperature regulating wool.



Grobag, The Sleep Store etc

(Cotton outer)


(Merino & organic cotton blend)

Ergopouch - Sleeping Bags

(Cotton outer and lining)

Bedroom Temperature

0.5 tog 1.0 tog Summer 3-Seasons

0.2 tog

0.3 tog

1.0 tog

30°c (86°f)


28°c (82°f)

    Singlet Nappy      

26°c (79°f)

Short-sleeved bodysuit   Short-sleeved bodysuit Singlet Singlet Singlet  

24°c (75°f)

  Short-sleeved bodysuit Short-sleeved bodysuit Short-sleeved bodysuit Short-sleeved bodysuit Short-sleeved bodysuit Short-sleeved bodysuit

22°c (71°f)

  long-sleeved bodysuit   Long-sleeved bodysuit     Long-sleeved bodysuit or All-in-one

20°c (69°f)

  Short-sleeved bodysuit & pj top   Long-sleeved bodysuit & pants     All-in-one, singlet & arm warmers

18°c (65°f)

      Long sleeved bodysuit, pants & top      

16°c (61)°f


14°c (57°f)



The bag lengths are measured at the start of the 2017 Summer season - some small variation may occur. The length measurement is taken from the shoulder to the bottom hem of the sleeping bag. Width taken at the widest part of the bag. Chest width measured accrossed the chest area. Back of neck measured across the back of the neck hole when the sleeping bag is laid flat. Find the latest prices and offers in our Sleeping Bag department here.


Is a Front Zip Sleeping Bag Better than a Side Zip or Diagonal Zip?

We often get asked whether the front or side zip bag is 'better''s really hard to say, as our customers have different views on this!

We find a bag with front zipper is much easier to use - simply pop your baby in and zip down the front (zips end at the bottom). Bags with front zips don't have the hassle of babies popping the shoulder domes, generally have smaller arm holes which are a closer fit and have no risk of the domes failing after lots of use. It's still easy to change a nappy with a front zip, as they are plenty long enough and the bags open wide enough to access the nappy.

Shoulder domes and side zip enable you to open the bag out flat. This can be easier for babies under 6 months who still need frequent night nappy changes. With babies who sleep through the night the easier nappy change isn't really a factor.

Some bags have domes on both shoulders (eg Woolbabe & grobag) and when combined with a long side-zip can fold out flat for faster drying after washing, others have 2 domes on one shoulder only.

For further details and customer testimonials on Front vs Side-zip click here.


Sleeping bag features explained:


Woolbabe sleeping bags use a unique fabric knitted especially for woolbabe from 30% merino and 70% cotton. This feels like a cotton T-shirt but contains enough merino that it really helps regulate your baby's temperature. This fabric can help babies stay the right temperature, covers a wide room temperature range and stays comnfortable even if it gets damp.


Weight & Size:

Choose a sleeping bag for the size and weight your child is NOW. Sleeping bags need to be the right size to be a safe fit and we do not recommend buying a bag to 'grow into'.  Sizing differs for each brand, so please check the table above or see each product page for details. In particular, the 2-4 year woolbabes should not be used for children under 12kg and we recommend waiting until 2 years old as they are a big fit and are very long.

Age ranges can vary in size between manufacturer however use the following info as a guide 0-6m or at least 4kg, 6-18m or at least 8.1kg, 18-36m or at least 11.4kg and 3-6 years or at least 55cm chest.


  Woolbabe The Sleep Store Ergopouch Nature Baby Grobag Slumbersac Love to Dream Burrow & Be
Age Range 3-24 Month 3-24 Month 2-12 Month 0 - 24 Months 6-18 Month 6-18 Month 4-12 Month 6-18 Month
Length 100 cm 100 cm 82 cm 90 cm 87 cm 89 cm 79 cm 81 cm
Width 44 cm 44 cm 43 cm 51 cm 51 cm 49 cm 47 cm 45 cm
Chest Width 34 cm 34 cm 32 cm 27 cm 27 cm 29 cm 24 cm 29 cm
Back of Neck 10 cm 10 cm 10cm 10 cm 10 cm 11 cm 13 cm 11 cm


Warmth Rating:

Sleeping bags generally come in 3 weights - Summer (also called 0-3 & 0.6 tog), Mid-weight (3-seasons, 1.0 tog etc) and Winter weight (duvet, winter, 2.5 & 3.5 tog).  For most houses, you will need more than one weight of sleeping bag to ensure your child sleeps comfortable.

The only bag which gets close to being a 'year round' bag is the 3-seasons woolbabe, which we have personally used in rooms 18-28 degrees. However if your child's room is regularly in the high 20's we recommend investing in a summer sleeping bag.

Fabric & layers:

Summer sleeping bags are either one or two layers of fabric.

They can be made from either jersey fabric (stretchy like a T-shirt) or Woven cotton (like sheets, sometime referred to as sheeting fabric).

Our summer bag range includes 100% cotton - in a variety of weaves and Woolbabe's unique Merino and organic cotton blend.

Buggy Slot:

Some of our summer sleeping bags have a 'Buggy slot', which means you can use the bag in a buggy with 5 point harness. These bags are all clearly labelled in the product description page. You can of course use buggy slot bags in your cot as normal.

Front zip travel bags have a double-ended zip on the front and buggy slot in the back. Side zip travel bags have slots in both the front and back of the bag.

Eczema Friendly options:

Our own brand 100% organic cotton range is a standout option here is you are looking for a generously sized option that's soft against the skin.

ErgoPouch is also a consideration for a more snug fitting bag.


What size sleeping bag do you need?

Please choose the right size for your baby now, not for the future. While it may seem better value to buy something your baby will 'grow into', you risk buying something that is not safe now. With a sleeping bag that is too big, your baby may slide round inside it or slip down inside the neck.

Generally sleeping bags & sleep sacks are available in 0-6 months, 6-18 months and 18-36 months. Most Merino bags are available in 3 months to 2 years and 2-4 years. The actual size of the sleeping bag within each age range can vary, for example, some sleeping bags sized for use from newborn can be used up to 12 months in some cases where as other are shorter and may only fit up to a 6 month old. 

For more details on the sizing from our most popular brands click the link below. Remember to measure your child from shoulders to feet rather then head to toe. The measurements below are just for the most popular size range, other size options available in each of the styles.


Compare Sleeping Bag Brands & Styles

The Sleep Store carries a wide range of sleeping bags, the best we can find!  This can be confusing if you are new to sleeping bags. We aim to give you a range of fabrics, styles, composition and of course the all important budget!

While a couple of brands are better known, all our bags have a point of difference and all meet our standards for quality and durability that may make them the perfect option for your baby! Don't assume you need the most-well known or expensive brand as that's what you have heard of or all your parents group have!

Click here for our full article on comparing sleeping bag brands to help you choose the right one: 

To Shop our most popular sleeping bag brands click the brand names below.


Shop Sleeping Bags