This post may contain affiliate links. If you buy through them, I may earn a small commission at no extra cost to you, which helps support the site. All opinions are entirely my own. Written by Molly, mum of two. Last updated: 22 October 2026.
If you’re anything like me, you’ll know the nightly battle of trying to keep your baby warm without overheating, while also stopping them kicking off their blankets and waking up cold. A baby sleeping bag (or sleep sack) solves both. The tricky bit is working out which TOG to use, especially once the heating goes on and the nights get colder.
Below you’ll find a simple TOG chart, what to dress your baby in underneath, and the sleeping bags worth buying in 2026. To complete your baby’s sleep setup, also see my guides to the best white noise machines, best blackout blinds and best baby monitors.
In a Hurry? Quick Picks
- Best overall: Tommee Tippee Original Grobag
- Best for winter: Mori Clever Sleeping Bag 2.5 TOG
- Best for night-time nappy changes: Ergobaby Sleeping Bag
- Best for newborns: Love to Dream Swaddle Up
- Best for toddlers on the move: Slumbersac Sleeping Bag with Feet
- Best budget: TU Baby Sleeping Bag at Sainsbury’s, from £12
What TOG Sleeping Bag Does My Baby Need?
TOG is just a measure of how warm the bag is. The higher the number, the warmer it is. The Lullaby Trust recommends keeping your baby’s room between 16°C and 20°C, so a cheap room thermometer near the cot is the easiest way to get this right. Then match the TOG to the room:
| Room temperature | TOG | What to wear underneath |
|---|---|---|
| Above 24°C | 0.2 to 0.5 | Short-sleeve vest, or just a nappy on very hot nights |
| 20 to 24°C | 1.0 | Babygrow, plus a short-sleeve vest at the cooler end |
| 16 to 20°C | 2.5 | Babygrow, plus a vest at the cooler end (long-sleeve at 16°C) |
| Below 16°C | 3.5 | Babygrow, plus a sleeveless vest if it’s really cold |
For most UK homes in winter, a 2.5 TOG is the one you’ll use most. A 1.0 TOG covers spring, autumn and warm houses, and a 0.2 or 0.5 TOG is only really needed in heatwaves (my guide to keeping baby cool at night covers summer).
To check if your baby’s too hot or cold, feel their chest or the back of their neck, not their hands or feet, which are often cool. Sweaty or hot to the touch means take a layer off.
What to Look For in a Baby Sleeping Bag
- A snug fit at the neck and shoulders: your baby’s head shouldn’t be able to slip down inside the bag.
- The right size: buy for your baby’s current age or weight, not one to grow into.
- No hood: and no extra blankets on top. A sleeping bag replaces bedding, it doesn’t add to it.
- Not weighted: avoid weighted sleeping bags and sleep suits.
- The safety standard: look for BS EN 16781:2018 on the label.
- Zip: a two-way or bottom-opening zip makes 3am nappy changes much less disruptive.
- Breathable fabric: cotton, bamboo or merino help stop them overheating.
| Sleeping bag | TOG options | Price | Best for |
|---|---|---|---|
| Tommee Tippee Grobag | 0.2, 1.0, 2.5 | From £23 | All-rounder |
| Mori Clever 2.5 TOG | 2.5 | £56 to £70 | Winter |
| Ergobaby | 1.0, 2.5 | £30 to £40 | Nappy changes |
| Love to Dream Swaddle Up | Several, inc. 1.0 | £27.99 | Newborns |
| JoJo Maman Bébé Sleep Snuggler | 2.5 | £39.50 | Cold rooms |
| Slumbersac with Feet | 1.0 | From £35 | Toddlers |
| TU Baby (Sainsbury’s) | 2.5 | From £12 | Budget |
The Detailed Reviews
Tommee Tippee Original Grobag
The Grobag is the one most UK parents start with, and for good reason. It comes in 0.2, 1.0 and 2.5 TOG, so you can buy the same bag for every season, and it has inner zip covers so the zip can’t rub your baby’s skin.
- Every TOG you’ll need, in sizes up to 36 months
- Soft, breathable cotton
- Zip covers for safety
- Good to know: a bit bulkier than some, and the designs are fairly basic
Price: from about £23.
Best for: a dependable everyday bag for every season.
Mori Clever Sleeping Bag 2.5 TOG
My pick for winter. The Mori is made from a soft bamboo and organic cotton blend that’s breathable and helps regulate temperature, so it’s warm without being sweaty. It’s one size from 4kg up to 2 years, with poppers on the armholes to adjust the fit as your baby grows.
- One bag from 4kg to 2 years, so it works out good value
- Two-way zip and a side shoulder opening
- Has a gap for a pushchair harness, handy for car seat to cot transfers
- Good to know: it’s pricier upfront, and you shouldn’t hang it to dry as the bamboo can stretch
Price: £70, often on offer for around £56.
Best for: cold nurseries and parents who prefer natural fabrics.
Ergobaby Sleeping Bag
The Ergobaby has a two-way zip, so you can change a nappy without taking the whole bag off and waking everyone up. The bamboo-cotton blend is breathable, which is great for babies who run warm.
- Two-way zip for quick night changes
- Breathable bamboo-cotton blend
- Comes in 1.0 and 2.5 TOG
- Good to know: no summer TOG, and the fit is slightly narrow for bigger babies
Price: around £30 to £40.
Best for: hassle-free night-time nappy changes.
Love to Dream Swaddle Up
The Swaddle Up lets newborns sleep with their arms up by their face, which is how lots of babies naturally like to settle. It’s stretchy, easy to zip on, and a much simpler option than wrapping a traditional swaddle at 2am.
- Arms-up design so babies can self-soothe
- Soft, stretchy cotton blend
- Good to know: stop using any swaddle as soon as your baby shows signs of rolling, and move to a sleeping bag with arms free
- Good to know: some babies just don’t like it
Price: £27.99 RRP.
Best for: newborns, and babies moving on from traditional swaddling.
JoJo Maman Bébé Sleep Snuggler 2.5 TOG
A cosy winter option that comes with matching booties, which is handy if your baby’s feet always feel cold. Sizes run from 6 months up to 3 years.
- Warm 2.5 TOG with booties included
- Sizes up to 3 years
- Good to know: some parents find the zips fiddly in the dark
Price: £39.50.
Best for: chilly bedrooms in the depths of winter.
👉 Check price at JoJo Maman Bébé
Slumbersac Sleeping Bag with Feet
Once your toddler is walking, a normal sleeping bag can turn bedtime into a battle. The Slumbersac has legs and foldable cuffs with non-slip soles, so they can toddle about at bedtime and still stay covered all night.
- Legs and non-slip feet for walkers
- Fold-over cuffs to cover feet at night
- Good to know: it’s quite snug, which not every toddler likes
Price: from about £35.
Best for: toddlers who climb out of, or refuse, a normal sleeping bag.
TU Baby Sleeping Bag (Sainsbury’s)
Proof you don’t need to spend a fortune. Sainsbury’s own TU sleeping bags start at around £12 for a 2.5 TOG, in sizes up to 24 months. They’re a great cheap spare for when the main one’s in the wash.
- Very low price
- Easy to pick up with the food shop
- Good to know: nappy changes are harder than with a bottom-opening zip
Price: from £12.
Best for: a budget main bag or a spare.
Baby Sleeping Bag FAQs
What TOG sleeping bag should my baby use in winter?
For most UK homes with the heating on, a 2.5 TOG. Only go up to 3.5 TOG if the room drops below 16°C, and check the room temperature rather than guessing.
Can I put a blanket over a sleeping bag?
No. A correctly fitting sleeping bag replaces blankets. If your baby feels cold, add a layer underneath or switch to a higher TOG instead.
Should my baby wear a hat to sleep?
Not indoors. Babies lose heat through their heads, which helps stop them overheating, so leave hats off for sleep.
How do I know if my baby is too hot?
Feel their chest or the back of their neck. If it’s sweaty or hot, take a layer off. Cold hands and feet are normal and don’t mean they’re too cold.
How many sleeping bags do I need?
Two in the TOG you use most (usually 2.5 in winter), so there’s always one clean after a nappy leak, plus a 1.0 TOG for warmer months.
What’s the difference between a sleeping bag and a sleep sack?
Nothing, they’re the same thing. “Sleep sack” is the American name, and in the UK they’re usually called baby sleeping bags or Grobags.
For more sleep help, see all my picks on the sleep reviews page, my 10 baby essentials that aren’t a waste of money, or browse my full approved products guide.
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