Selecting the Right Sleeping Bag for Backpacking Adventures

When I first began backpacking, selecting the right gear felt incredibly daunting. At first glance, it might seem simple—like just picking a sleeping bag—but the reality involves dozens of small decisions, each with its own complexities that can quickly become overwhelming. So how do you even begin?

By identifying the environments you’ll most often encounter while backpacking, this guide can help you reverse-engineer the ideal bag for your needs. While other elements—such as base layers and sleeping pads—can influence your sleep system, this approach provides a strong foundation to begin with.

Settling in for the night along the CDT in Colorado with my Zpacks Classic 5 degree sleeping bag.

How to decide between synthetic and down sleeping bags

When choosing a sleeping bag, one of the initial choices you’ll face is whether to opt for down or synthetic insulation. Both options have advantages and drawbacks, but down is typically the preferred choice for long-distance backpacking. To see why, consider the benefits of down sleeping bags. Most notably, down offers superior warmth-to-weight ratio compared to synthetic alternatives, making it the ideal choice for lightweight insulation. Additionally, down compresses more efficiently, saving valuable pack space—freeing up room for essentials like food. With proper maintenance, including correct washing and storage, a down sleeping bag can also outlast synthetic models, providing reliable performance for years.

You might wonder, are down bags flawless? While they’re excellent, they do have some downsides. A significant issue is that down loses its insulating properties when wet. If your sleeping bag gets drenched in a downpour, you’ll need an alternative for the night. Quality shelters and backpacks can help avoid this, but it’s a crucial consideration for trips in persistently wet and chilly environments (like the late shoulder season in the North Cascades). Down bags also demand careful upkeep—they need specialized detergents for washing and shouldn’t be stored compressed. Additionally, down is pricier than synthetic, though with proper care, it offers long-term durability. Lastly, down allergies can make it a non-option for some.

This highlights the advantages of synthetic insulation. Unlike down, the synthetic materials in sleeping bags resist water and retain warmth even when damp, making them perfect for situations where moisture is inevitable. Additionally, synthetic bags tend to be more budget-friendly than down-filled ones, as their materials are simpler to obtain—no geese or ducks required. Lastly, synthetic is the better choice for those with a down allergy.

That said, synthetic filling naturally comes with its own drawbacks. It provides less warmth and adds more weight. Its bulkier nature makes it unsuitable for backpacking, where minimizing weight and saving space are key considerations. Additionally, synthetic insulation is far less durable than down—its insulating capacity diminishes slightly with every compression.

What should a backpacker choose? If your budget allows, opt for a down sleeping bag and be diligent about keeping it dry, especially in rainy conditions. My preferred method is using a trash compactor bag inside my pack—it’s lighter than dry bags and just as effective.

TLDR:

Down

Pros:

• Lighter for less warmth

• Compresses with ease

• With proper care, it can endure for many years.

With proper care, it can remain in good condition for many years.

Cons:

• Loses insulation effectiveness when exposed to moisture

• Necessitates specific upkeep

• Possible allergic reactions to consider

• Costing a greater amount

Synthetic

Pros:

• Able to resist water penetration

• Maintains insulation even when damp

• Hypoallergenic

Cons:

• Cooler temperatures for greater mass

• Large and cumbersome

• Loses insulating effectiveness gradually with prolonged use.

Spending the night at Capitol Lake using my Katabatic Sawatch 15-degree quilt.

Deciding between a quilt and a conventional sleeping bag: key factors to consider

Over the past few years, quilts have surged in popularity among backpackers. They’re innovative, stylish, and, most crucially—they offer a way to reduce your pack’s base weight by a few ounces. Yet what precisely defines them? And how do they stand apart from traditional sleeping bags?

A quilt functions similarly to a down blanket. It eliminates the back section of a sleeping bag, which typically lies beneath you. Since the insulation in that area gets compressed while you sleep, it offers minimal warmth. By using a quilt, you avoid carrying excess insulation and fabric, lightening your load without sacrificing much—if any—heat retention. Many quilts feature snug foot boxes and additional straps to secure them around your sleeping pad, minimizing drafts and ensuring warmth throughout the night. That said, designs vary, and some quilts may be prone to drafts, so checking reviews before purchasing is advisable.

Since everyone likely knows what a typical sleeping bag looks like, I’ll keep this short. The key distinctions are between mummy bags (featuring enclosed hoods) and non-mummy bags. Mummy bags excel for winter camping and anyone who prefers feeling tightly wrapped up outdoors, though the additional fabric does increase the overall weight.

No matter the circumstances, conventional sleeping bags will zip completely shut and invariably feature enclosed foot compartments, reducing the likelihood of drafts.

The decision ultimately depends on personal preference. If you enjoy being snugly wrapped like an infant while sleeping, you probably lean toward the mummy bag side. If you prefer the flexibility to sometimes kick a leg out from under the covers, quilts might suit you better. Many suggest that quilts are ideal if you move around frequently at night, but I disagree. In my view, this increases the risk of drafts, making a conventional sleeping bag a more reliable choice. While opting for a quilt can sometimes reduce weight slightly, that isn’t always the case.

Sleeping under the stars in the Grand Canyon with my Katabatic Sawatch 15 degree quilt.

Selecting the right temperature rating for your sleeping bag

A temperature rating shows the minimum temperature at which a sleeping bag can keep an average person warm. For instance, a 5-degree bag ensures comfort at 5 degrees but not below. It also means a 5-degree bag provides more warmth than a 30-degree one. As a beginner backpacker learning about temperature ratings, I noted two important points—standardization of these ratings matters (more on that later), and it’s helpful to know how your own tolerance compares to the average. I tend to feel cold easily; even slight chills make me shiver, so I prefer a bag rated 20-25 degrees warmer than the actual temperature for true comfort. Sure, I could probably endure the stated rating, but we’re not outfitting for survival—this is about enjoying the trip. That’s why, to stay cozy in 30-degree weather, I’d choose a 5-degree bag.

Let’s discuss temperature rating standards—without them, sleeping bag manufacturers could simply assign arbitrary temperature ranges to their products. The two primary standardization systems are EN (European Norm) and ISO (International Organization for Standardization). These widely recognized benchmarks typically include a “comfort” rating (ideal for cold sleepers like me) and a “limit” rating (suited for those fortunate warm sleepers who can use lighter bags). If a bag lacks one of these standardized ratings, it’s wise to choose a warmer option than usual and thoroughly check user reviews. Cooling down by loosening your bag or sticking out a leg is far simpler than dealing with the discomfort (or potential risks) of an insufficiently warm bag.

Appreciate your patience while I covered temp ratings—now let’s dive into the specifics of which temperature ratings to consider based on the season and regions you’ll be backpacking in.

A general guideline (adapt according to your individual comfort with temperature):

Sleeping bags rated for 20 degrees Fahrenheit or below:commonly utilized during colder seasons (winter, early spring, late fall) and in high-altitude environments.

Sleeping bags rated for temperatures between 20 and 32 degrees Fahrenheit:Ideal for transitional periods and alpine environments

Sleeping bags rated for 32 degrees Fahrenheit and higher:Utilized during the summer months and in lower-altitude regions

For an average sleeper in need of a three-season bag (ideal for a thru-hike), I’d recommend choosing one rated between 20 and 32 degrees.

From my own experience—I chose a 5-degree sleeping bag for the PCT since, as I mentioned, I’m constantly cold. It was slightly excessive in some summer stretches, but I’d simply leave the zipper open or treat it like a blanket on hotter evenings. The extra warmth proved invaluable by the time October arrived in Washington.

Camping cowboy-style in the San Juans along the CDT during late May (included a liner for additional warmth here).

Selecting the right fill power and fill weight for your sleeping bag

Fill power and weight are terms specific to down sleeping bags, and understanding these figures is essential when selecting your ideal sleep setup.

Loft capacitypertains to thequalityThe loft of the down is determined by the volume occupied by 1 oz of down. A higher fill power indicates a lighter and more compressible sleeping bag.

Net weightrefers to theamountThe amount of down is indicated by the ounces of down present in a comforter. Fill weight serves as the primary factor determining warmth.

Although fill weight primarily determines warmth, greater fill power enhances insulation efficiency with less weight.

In the simplest terms: Greater loft between the down fibers improves insulation, resulting in a sleeping bag that is both lighter and more thermally efficient.

When applying this concept: if you’re personalizing a bag designed for 10-degree conditions and must choose between 850 and 950 fill power—the 950 fill power will achieve a 10-degree rating with less fill weight compared to the 850 fill power option.

Selecting the right size for your sleeping bag

Selecting the right sleeping bag size is simple (refer to the gear company’s sizing guides), though there are a few helpful tips to consider.

Your height dictates the ideal length, though stomach sleepers should consider adding a couple of extra inches.

Width is calculated based on, as you might expect, your body’s width—usually by measuring the broadest section (with your arms resting naturally at your sides). If you tend to shift positions frequently while sleeping, remember to include an extra few inches for comfort.

Pro tip: because many cottage gear brands are sold exclusively online and it can be tough to judge comfort beforehand, you have two options: 1) visit a retailer such as REI to try out bags in person (and take note of their dimensions) or 2) use safety pins to adjust a sheet at home and simulate different widths to gauge comfort.

How to select a sleeping bag considering weight and price

This is where it becomes tricky. Nearly every decision you make will influence these two critical aspects. An ideal weight for a down backpacking sleeping bag is less than 2 pounds, though lighter options usually come at a higher price. In my opinion, it’s wise to spend on high-quality equipment you’ll appreciate, since purchasing a single $400 bag is more economical than buying three at $150 each.

The least expensive bags are usually heavier synthetic options, whereas lightweight down bags tend to be more costly.

If you’re just starting out with backpacking and hesitant to invest in a high-end, 950 fill power, 10-degree, $400 down sleeping bag—check out second-hand choices on Facebook Marketplace or resale platforms. Certain cities also feature gear consignment shops offering quality pre-owned equipment at budget-friendly rates. Additionally, planning ahead allows you to take advantage of sales (Black Friday is an excellent opportunity to purchase off-season gear).