Sea to Summit

Spark Ultralight Sleeping Bag

Sea to Summit Spark Ultralight Sleeping Bag

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Overall

#53 in

Outdoor Sleeping Bags

according to Reddit Icon Reddit

Sentiment score65% positive
15
2
6
Last updated: Jun 21, 2026

Reddit Reviews

Reddit IconAlaskanarrowusa
6 months ago

My three recommendations: - Sea to Summit Spark SpII/SpIII (long versions) - Western Mountaineering UltraLite - Mont-Bell Down Hugger 800 #3 Another down option with a bit more room for comfort is the Big Agnes Lost Dog 15 (Long) which is fluffier than pure ultralights, compresses fairly well and hits that 3-season range without feeling like a coffin too! [9 Best Sleeping Bags in 2025 for Camping and Backpacking](https://alaskanarrows.com/best-sleeping-bags-for-camping-and-backpacking/) for other options as well Hope this helps

6 months ago

My three recommendations: - Sea to Summit Spark SpII/SpIII (long versions) - Western Mountaineering UltraLite - Mont-Bell Down Hugger 800 #3 Another down option with a bit more room for comfort is the Big Agnes Lost Dog 15 (Long) which is fluffier than pure ultralights, compresses fairly well and hits that 3-season range without feeling like a coffin too! [9 Best Sleeping Bags in 2025 for Camping and Backpacking](https://alaskanarrows.com/best-sleeping-bags-for-camping-and-backpacking/) for other options as well Hope this helps

Reddit IconBottleCoffee
4 months ago

The 45° S2S Spark is a lot more expensive but it compresses to 2.4 L. https://seatosummit.com/products/spark-down-sleeping-bag

Reddit Iconjmedina37
11 months ago

Spark 0 is great. Used it down to 8F this winter and was still toasty warm

Reddit IconLetMany4907
9 months ago

Sea to Summit Spark 0° for cold trips. It’s lightweight, packs tiny, and still keeps me warm in sub-zero temps. Make sure it has a draft collar and insulated hood, they make a huge difference when it’s windy. Test it at home first to make sure you’re comfortable.

Reddit IconLordRaiders
7 months ago

Hey everyone, I want to get into backpack hiking in Australia (Victoria) mostly in summer and spring but want the option to go in Autumn too. The weather here is not too cold but can get around 0*C during the night. I am 6’6 (1.98cm) and find that most sleeping bags are too short for me. I tried the Sea To Summit Spark which is just too tight. I consider looking at a quilt (which is usually lighter too as I understand) but I am concerned they do not provide the same warmth unless you have a really expensive mat too. The Sea To Summit Ember seems like a reasonable option but is only marked as a 2 season on their website. Does someone have a recommendation on either a sleeping bag or quilt? Budget is not set in stone yet but given that I am just starting I am not really looking at the top end A$700 bags.

Reddit Iconrestroom_raider
4 months ago

I’ve got a Sea to Summit Spark II, which is excellent - I’ve used it for random tramps, and bikepacking events like the Great Southern Brevet, Kiwi Brevet, etc. One night, we had torrential rain and snow come through, and I was fine in the bag (this was in an open fertiliser shed/lean to in Central Otago) OGR has huts, so minimum temp isn’t such a problem, and if you’re looking for a good 3 season bag, something similar to the Spark II would be a good bet (they’re no longer made, from what I can tell). Mine is ~10 years old and just as good as the day I bought it, which is why I recommend the brand. Also worth looking for a decent sleeping mat - it’ll make as much difference as a good bag, if it’s insulated. I use a mummy shaped Exped mat, rolls up about the size of a bidon and weighs ~400g. IMO it’s worth investing in a good sleep system, I’ve had my stuff long enough that it has cost $100/year at this point.

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