Stuff Sacks and Compression Bags

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Why are stuff sacks important?

Long distance backpacking requires minimizing excess weight and accessories whenever possible. Instead of using clunky commercial packs with loads of unnecessary pockets and compartments, most ultralight backpackers prefer minimalist backpacks paired with a few stuff sacks for organization.

Compartmentalize. Proper organization saves a lot of headache. Reaching for your stove as hunger strikes, grabbing an extra layer when the sun sets, etc. Stuff sacks will keep your gear segmented into different 'groups'.

Water Protection. Yes, your pack should already have some waterproof barrier - a pack cover, liner, etc. However, it is super important to add an extra layer of protection to your gear. You never know when your liner has a leak, until all of your gear is drenched. Stuff sacks will help ensure your most important items (clothes, sleeping bag, electronics, etc) are dry when you reach camp.

Lighter Weight. Consolidating your gear into a few bags can save several ounces, if not pounds. Switching from factory issued compression bags to higher quality and more specialized stuff sacks can save even more weight.

Portability. It is much easier to bring a small bag with your food in it to the campfire, instead of your entire pack.

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How many stuff sacks do I need?

It can vary depending on your gear, weather conditions, pack size, etc. I generally recommend using four or five though.

1. Food. A 15 liter sack can provide up to a week's worth of food storage. Unless you have some serious pest problems or are on the water, a drawstring closure is best. 

2. Clothes. Pack away your clothes at night in this one and use it as a pillow. Several companies make fleece lined stuff sacks for a comfortable head rest.

3. Sleeping Bag. Your sleeping bag is your safety blanket, quite literally. Therefore, it must stay dry at all costs... especially in winter. Get a roll top sack for waterproofing as well as some compression straps to minimize the bulk. If possible, do not store your sleeping bag compressed for a long period of time. It will lose it's loft and, subsequently, lose it's insulation ability.

4. Extras. Your kitchen (stove, pot, fuel) might need it's own bag. You might have your own mini wallet bag... or a toiletries bag. You might want an overall miscellaneous bag for any loose ends like headlamp, journal, fire starter, electronics, etc. Just personal preference. Note small zip sacks are often called "pods".

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Things to Consider

Weight-to-Volume Ratio. Your backpacking pack will have a carrying capacity of about 50 to 65 liters. Therefore, unless you use one as a pack liner, you probably won't carry any sacks larger than 20 liters. As a rule of thumb, for every ounce of stuff sack weight, you should get 10 liters of carrying capacity.

Example: a 15 liter stuff sack should weight about 1.5 oz.

No "Manufacturer Sacks". Keep in mind most factory issued stuff sacks  (example: the sack your sleeping bag comes in) are heavy, poor quality and/ or not waterproof. If yours is any of these, consider getting something more specialized for gear storage.

Compression. Compression bags are a type of stuff sack that are used to minimize the volume or space of a particular gear item. They are most commonly used to reduce the bulk of a sleeping bag in your pack. Most come with 3 to 4 lines or straps to cinch down.

Roll Top vs Drawstring. Roll tops are good for gear that need an airtight enclosure - waterproof, bug proof, etc. This airtight enclosure also enables it to be used as a makeshift compression bag without any additional straps.

Drawstrings are lighter. They are also much faster and easier to open and close. Easy access to your gear makes them a much more popular stuff sack option.

Quality Material. There are several options. Like most backpacking gear, stuff sacks and compression bags are usually made from Dyneema (formerly 'Cuben Fiber') or Ripstop Nylon. They are both durable, waterproof and lightweight.

Carrying Capacity. Most are measured in liters. You can get a stuff sack tiny enough just to protect your cell phone as well as one big enough to line your entire pack with. Know exactly what you intend to use it for.

The Best Lightweight Stuff Sacks

GRANITE GEAR

The eVent Uberlight Drysack gets my vote for the best stuff sack. Offered in 4 different sizes (7L, 10L, 13L, 18L), these waterproof, roll top sacks weigh nearly half of the weight-to-volume ratio outlined above. This is impressive for any stuff sack, but especially for a roll top. It's rectangular shape packs better than other, more cylindrical, sacks. Add compression straps from image if desired. 
See Granite Gear Sack.

HYPERLITE MOUNTAIN GEAR

Hyperlite Mountain Gear makes a boat load of ultralight, Dyneema stuff sacks. From small drawstrings pouches and zipper sealed pods on up to large roll top pack liners, they offer whatever you need at an extremely high quality. Their fleece lined pillow sacks are the lightest out there. 
See All Hyperlite Sacks.

GOBI GEAR

A unique piece of gear. Gobi created the Segsac as a way to help compartmentalize... the compartment. This extra material will definitely add a few extra ounces to your load. However, the extra organization might be worth it for a more casual backpacker. 
See Gobi Gear SegSac.

YAMA MOUNTAIN GEAR

If there ever was an "iconic emblem of the stuff sack", Yama's Penguin would be it. In addition to a little bit o' personality, these are really great for gear storage. They are ultra-lightweight and waterproof. Their assortments are very affordable relative to how expensive this Dyneema is as well. 
See All Yama Sacks.

OUTDOOR RESEARCH

Outdoor Research provides the most bang for your buck. Using Ripstop Silnylon, these are very high quality bags offered for a fraction of the price of others on this list. I have personally used this one for over 4 years and several thousand miles of backpacking. 
See OR Sack.

OSPREY

A new product offered by the king of backpacking brands, Osprey. Similar to Granite Gear, this is shaped like a rectangular prism. I love the shape because it rests flush in the bottom of my pack. Offered in black, blue, red and yellow and several sizes ranging from 3 to 30 liters. Drawstring closure and 40D Ripstop Nylon material. 
See All Osprey Sacks.

ZPACKS

Like Hyperlite and Yama, ZPacks also offers high-quality, ultralight, Dyneema backpacking gear. From tent stake bags to slim clothing bags to bear hanging food bags, there is a wide range to chose from. 
See All ZPacks Sacks.

THERM-A-REST

This stuff sack pillow is the most popular of it's kind on the market. The double lined fleece/ nylon bag makes it highly functional as both a waterproof sack and a comfortable pillow. At 2.6 oz and 14 liter storage capacity though, you will sacrifice an extra ounce for that cushioned head rest. 
See Therm-a-Rest Pillow.

DIY/ ZIP-LOC

Who on earth wants to pay $30 for a simple bag? Yes, a plastic sandwich or gallon bag can also do the trick. Of course, they are less durable and will probably wear out a lot faster. But, they can be ideal for those smaller "extras" mentioned earlier like toiletries, condiments, electronics, etc.