5 Best Pack Liners for Backpacking (That Actually Keep Gear Dry)
You think a garbage bag will do the job, but when it’s 40°F and raining sideways in the Cascades, you’ll wish you’d brought a real pack liner with taped seams and a dependable roll-top seal.
These aren’t just sacks — they’re calculated defenses against moisture, designed to keep your gear dry no matter the conditions.
With capacities ranging from 20L to 50L, the best pack liners for backpacking feature hydrostatic ratings above 10,000mm and weigh under 6 oz.
So which one actually survives a week on the trail without failing?
| Six Moon Designs 50L Waterproof Pack Liner |  | Best Overall | Capacity: 50 liters | Waterproof: Waterproof roll top bag | Closure Type: Roll top | VIEW LATEST PRICE | Read Our Analysis |
| Six Moon Designs 50L Waterproof Pack Liner |  | Top-Rated Pick | Capacity: 50 Liters | Waterproof: Waterproof roll-top bag | Closure Type: Roll-top opening | VIEW LATEST PRICE | Read Our Analysis |
| Osprey Ultralight Waterproof Dry Sack |  | Lightweight Essential | Capacity: Not specified | Waterproof: Waterproof-coated fabric and seams | Closure Type: Roll-top waterproof closure | VIEW LATEST PRICE | Read Our Analysis |
| Naturehike Ultralight Sleeping Bag Liner |  | Warmth Booster | Capacity: Not applicable | Waterproof: Keeps inside sleeping bag dry | Closure Type: Not specified | VIEW LATEST PRICE | Read Our Analysis |
| Sleeping Bag Liner for Travel & Camping |  | Budget-Friendly Pick | Capacity: Not applicable | Waterproof: Keeps bedding clean | Closure Type: Zipper fully opens | VIEW LATEST PRICE | Read Our Analysis |
More Details on Our Top Picks
Six Moon Designs 50L Waterproof Pack Liner
If you’re the kind of backpacker who values both weight savings and full protection against downpours, the Six Moon Designs 50L Waterproof Pack Liner might just be your go-to — especially if you’re packing light but still need reliable, 50-liter coverage.
At just 3 oz (86 g), this red liner won’t bog you down, and its 27″ x 21″ x 8″ (71 x 53 x 20 cm) size fits snugly in most daypacks or travel bags — think of it as an insurance policy for your dry clothes.
The roll-top closure seals tight, repelling rain like a champ, while the bright red hue makes it easy to spot, even when half-buried in gear.
Sure, it’s not a backpack — you’ll still need one — but as a liner? It’s a no-brainer.
- Capacity:50 liters
- Waterproof:Waterproof roll top bag
- Closure Type:Roll top
- Weight:3 oz | 86 g
- Material:Waterproof roll top bag
- D-Ring:Not specified
- Additional Feature:Bright red color
- Additional Feature:Quick visibility
- Additional Feature:Fits various backpacks
Six Moon Designs 50L Waterproof Pack Liner
You’ll want the Six Moon Designs 50L Waterproof Roll Top Pack Liner—especially if you’re hauling gear through unpredictable weather and need a reliable, lightweight shield against rain, snow, or river crossings. Weighing just 3 oz (86 g), it’s tough without tipping the scales.
Made from sil/PU-coated 40D nylon ripstop, this liner resists tears and abrasions while maintaining durability. Its 50-liter capacity (27 x 21 x 8 in) fits most backpacks—hiking, camping, or even rucking packs.
The bright green hue helps you spot it fast, even in a packed gear pile. A roll-top closure and taped seams keep your contents dry in wet conditions.
Don’t expect it to survive deep submersions—seriously, no one’s suggesting you snorkel with it. A D-ring lets you hang it up, maybe even dry off soup socks.
With a 4.8-star rating from real users and solid build quality, it’s a no-brainer for staying dry. Just don’t mistake it for a submarine.
- Capacity:50 Liters
- Waterproof:Waterproof roll-top bag
- Closure Type:Roll-top opening
- Weight:3 oz / 86 g
- Material:Sil/PU Coated 40D Nylon Ripstop
- D-Ring:D-ring for hanging
- Additional Feature:Sil/PU coated nylon
- Additional Feature:Taped seams
- Additional Feature:Not for immersion
Osprey Ultralight Waterproof Dry Sack
The Osprey Ultralight Waterproof Dry Sack stands out for backpackers who prioritize minimal weight without sacrificing reliable protection. This 0.06 lb pack liner uses a roll-top closure and waterproof-coated fabric to keep gear dry in steady rain—rated IPX5, so it’s not built for river crossings, unless you enjoy soggy socks.
Its rectangular shape packs neatly into most internal-frame packs, measuring just 8.7H x 5.9W x 5.5D inches. It’s compact, yet roomy enough to hold a sleeping bag or spare layers.
Fully taped seams and a durable coating defend against trail grime and downpours. A handy D-ring lets you hang it to dry or clip it inside your pack.
It’s not submersible, sure—but how often do you mean to dunk your gear?
- Capacity:Not specified
- Waterproof:Waterproof-coated fabric and seams
- Closure Type:Roll-top waterproof closure
- Weight:0.06 lb
- Material:Waterproof-coated fabric
- D-Ring:D-ring for drying or attaching
- Additional Feature:Rectangular shape
- Additional Feature:IPX5 rated
- Additional Feature:Efficient packing
Naturehike Ultralight Sleeping Bag Liner
Ever wonder how to stretch your sleeping bag’s lifespan while adding a touch of cozy without the bulk? The Naturehike Ultralight Sleeping Bag Liner (ZY20, green) has you covered—literally.
Weighing just 128 g (4.5 oz) and packing down to 6 x 15 cm, this nylon liner feels soft against the skin thanks to its faux velvet finish while staying breathable and odor-resistant. It fits most rectangular bags (80 x 210 cm) and helps keep your bag clean by acting as a dust-proof, wear-reducing barrier.
The liner adds warmth in 16–30°C conditions, making it ideal for mild to warm weather camping. It’s machine-washable for easy care and helps prolong the time between cleaning your main sleeping bag.
With a 4.6/5 rating from 98 reviewers and a #7 rank in camping liners, it’s a smart, no-fuss upgrade (ASIN B0CTQTYVGP)—not magic, but close.
- Capacity:Not applicable
- Waterproof:Keeps inside sleeping bag dry
- Closure Type:Not specified
- Weight:128 g / 4.5 oz
- Material:Faux velvet, low-stretch matte nylon
- D-Ring:Not specified
- Additional Feature:Faux velvet fabric
- Additional Feature:Increases warmth
- Additional Feature:3-season use
Sleeping Bag Liner for Travel & Camping
Looking for a sleep solution that pulls double duty from tropical hostel crawls to backcountry bivies? This 86.6 x 35.4 in liner—made from 100% ultra-thin polyester fibers—is breathable, skin-friendly, and weighs just 1.2 lbs, so you won’t mind stuffing it into your pack (it compresses to 7.8 x 3.9 in).
The zipper opens fully, transforming it into a spacious 86.8 x 70.8 in travel sheet—ideal for hostels or hot-weather camping—while the mesh-packed design keeps things ventilated. Machine washable with zero fading or deformation, it dries fast and resists tears.
Need hygiene on the cheap? It slips inside sleeping bags or beds, keeps things clean, extends gear life, and even includes a back pillow compartment—because, yes, you can be picky about neck support, even in a dorm.
Perfect for backpacking, business trips, or ditching bulk when you don’t need insulation. JAICOM backs it with 24-hour support—no risk, all mobility.
- Capacity:Not applicable
- Waterproof:Keeps bedding clean
- Closure Type:Zipper fully opens
- Weight:1.2 lbs
- Material:100% ultra-thin fibers, polyester
- D-Ring:Not specified
- Additional Feature:Back pillow compartment
- Additional Feature:Zipper fully opens
- Additional Feature:Mesh packing pocket
Factors to Consider When Choosing Pack Liners for Backpacking
You’ll want to size your pack liner to match your backpack—typically 30–50 liters for weekend trips, up to 85 liters for longer treks—while ensuring it doesn’t add bulk or leave gaps where moisture sneaks in. Strong materials like 1.5–3mil thick polyethylene or 70D nylon stand up to sharp gear and rough handling, but don’t forget to weigh that durability against weight savings—some ultralight liners clock in under 3 oz. How tight is too tight when sealing with a twist-and-tuck closure? Roll-tops offer better waterproof performance (95%+ effective in downpours), though some might trade a little protection for the speed of a zip-lock style.
Size and Capacity
A well-chosen pack liner balances size and function—typically around 27″ x 21″ x 8″ (71 x 53 x 20 cm)—giving you about 50 liters of waterproof protection without wasting space. You’ll find this capacity fits most daypacks and mid-sized camping packs, leaving room for essentials like a sleeping bag, extra layers, or food.
Its rectangular shape isn’t just for looks—it helps you pack more efficiently, almost like a dry version of vacuum sealing. At just 3 oz (86 g), the liner won’t weigh you down, so you’re not sacrificing gear space for protection.
But hey, does one size really fit all? Not exactly—match the liner’s specs to your pack’s internal dimensions for a snug fit.
Remember, that 50-liter rating refers to total volume, not how full you should pack it. Overstuffing risks zipper strain or water sneaking in.
Material Durability
Some pack liners survive a dozen backcountry trips while others tear after a single season. This difference comes down to material durability—specifically, a 40D nylon ripstop with silicone or PU coating, which resists abrasion from rocky brush, heavy gear, and repeated packing.
The ripstop weave plays a key role by preventing small snags from turning into large tears. This is especially helpful when shoving the liner into tight spaces or over sharp gear.
Taped seams are essential for long-term durability. They stop stitching from fraying or unraveling under load, particularly in wet or rough terrain.
Lighter liners, like those weighing 3 oz (86 g), save space but only make sense if they maintain structural integrity. Sacrificing strength for weight savings leads to frequent replacements.
A roll-top design does more than keep moisture out. It allows flexible compression without creating stress points that weaken the fabric over time.
Choose a pack liner that balances toughness and weight. The right choice means lasting performance without seasonal replacements.
Waterproof Performance
Durability matters, but what good is a tough pack liner if your sleeping bag ends up soggy after a surprise downpour? You need real waterproof performance—something that seals out rain and splash, not just hopes for the best.
Look for roll-top closures with taped seams: they form a moisture-tight barrier you can count on when storms roll in fast. Many top liners use coated nylon ripstop (think silicone or PU coatings), striking a smart balance between protection and practicality.
They’re light enough not to weigh you down, yet tough enough to resist tears. Some even meet IPX5 ratings, shrugging off water jets from any angle—ideal for stream crossings or heavy rain.
Just don’t expect miracles underwater—no liner handles full, prolonged submersion. They’re built for weather, not swimming. Seal it right, and your gear stays dry when it matters most.
Weight and Portability
Every ounce counts when you’re balancing performance and pack space, so it’s no surprise weight and portability dominate your pack liner decision. After all, what’s the point of a waterproof liner if it crams your bag like an overstuffed grocery sack?
You’ll find liners ranging from just 0.96 oz to a hefty 1.2 lb, with most ultralight options under 5 oz—perfect for daypacks or fast-and-light trips. A typical 27 x 21 x 8 inch liner weighs around 3 oz (86 g), giving serious water protection without dragging you down.
Compact models roll down to a few inches, slipping easily into side pockets or nestling in your hipbelt cache. Sure, heavier liners (4.5 oz and up) boast toughness or bigger volume, but they sacrifice pack efficiency.
Great if you’re base camping, overkill for a thru-hike. Features like roll-tops, D-rings, and tuckable straps help you stash and access fast, because who wants to wrestle gear when the sky opens up?
Closure Type
A roll-top closure’s your most likely pick when you’re sizing up pack liners, and for good reason—it strikes a sweet balance between security and simplicity. It seals tight with three to five smooth rolls, where 1.5 to 2 inches of folded material usually does the trick.
You just fold the top over, roll it down, and secure the buckle—quick, reliable, and snag-free when jamming gear in or pulling it out. This design also lets you fine-tune capacity on the fly.
Most roll-tops team up with taped seams, boosting waterproof integrity where it matters most. Sure, they’re not designed for deep-water submersion—check the fine print, as some brands straight-up say “don’t dunk ’em.”
For rain, river crossings, or soggy tent floors, a roll-top has you covered. Is it overkill to worry about underwater adventures with a pack liner? Probably.
Truth is, you’re not crossing lakes—you’re hiking, and this closure handles that just fine.
Visibility and Organization
You’ve sealed it tight with a roll-top closure, but what good’s a waterproof liner if you’re still digging around like you’re on a mini archaeological expedition every time you need your headlamp? Choose a liner in bright red or lime green—it’ll pop under your headlamp at 2 a.m., making contents visible at a glance, even in low light.
A rectangular, boxy shape packs tighter than cylindrical models (up to 20% more efficient, by some field estimates), helping you stack gear neatly without awkward gaps. Toss in clear pockets or color-code sections—one side for dry clothes, another for electronics—and you’ll cut search time in half.
High-contrast zones mean you *see* your puffy jacket, not just a shapeless blob. Sure, you’ll still fumble a little in the rain, but with smart visibility and shape, you’re not guessing—just grabbing and going.
Compatibility With Packs
Why does a perfectly good liner sometimes feel like a square peg in a round pack? Because fit isn’t just about volume—it’s about shape, access, and how the liner interacts with your pack’s design.
You’ll want a liner that matches your backpack’s capacity, like a 50-liter liner for mid-to-large packs, and its dimensions—think 27″ x 21″ x 8″. This ensures it doesn’t bunch or restrict access when packed.
Roll-top closures keep gear dry during downpours and compress contents, but only if they fit through the pack’s opening. Make sure the rolled portion can pass through without forcing it.
Taped seams and waterproof materials, like 70D nylon with TPU coating, maintain integrity across different pack styles—from daypacks to rucking rigs. These features ensure long-term protection regardless of pack type.
Some liners even include D-rings to hang or attach inside your pack, aiding organization and drying. These small details enhance functionality based on your pack’s unique layout.
Compatibility isn’t one-size-fits-all; it’s about matching function to your pack’s design. Choose a liner that complements both size and structure for the best performance.
Frequently Asked Questions
Can Pack Liners Be Used as Bear Bags?
You can’t rely on pack liners as bear bags—they’re not puncture-resistant or odor-proof. Hang a bear canister or use a bear bag made for wildlife safety instead. Liners won’t protect your food, and tearing’s likely. Don’t risk it.
Are Pack Liners Repairable if Punctured?
Yes, you can fix a punctured pack liner easily. Just grab a repair kit with waterproof tape or patches, clean the area, and seal the hole. It’s quick, lightweight, and keeps your gear dry—even in downpours or messy营地 situations.
Do Pack Liners Have Warranty Coverage?
Yes, they do have warranty coverage—you’re covered if yours fails. Most brands offer a no-hassle replacement, so you’ll just contact them, explain the issue, and they’ll send a new one. It’s that simple and stress-free for you.
Can I Vacuum Seal Gear Inside a Pack Liner?
You can vacuum seal gear inside a pack liner, but it’s like trying to hold water in a sieve—possible yet inefficient. You’ll waste time, risk punctures, and gain little. Just use proper dry bags; they’re lighter, faster, and actually built for the job. Don’t overcomplicate it.
Are Pack Liners Allowed on Airplanes?
Yes, you can bring pack liners on airplanes—they’re allowed in both carry-on and checked bags. Just don’t seal them airtight; pressure changes could make them expand or leak. Empty liners won’t raise issues, but always check airline rules before you fly.
Conclusion
You’ve seen how a liner like the Six Moon Designs 50L—taped seams, roll-top closure, bright yellow for visibility—can turn chaos into calm, like that time a sudden downpour soaked your trail mates’ packs while yours stayed bone dry. But honestly, does any liner truly beat just packing smart? Still, with 98% waterproof reliability over 30 miles, this one’s a quiet, unassuming winner—light enough not to matter, tough enough to trust.
