Anyone who’s backpacked a long distance knows there’s no perfect way to keep your gear dry. Pack covers are clunky, and blowing rain can come in from the sides. A waterproof pack is a good option, but they are usually made with Dyneema Composite Fabric and are very pricey. Pack liners are a simple, lightweight option that keeps the main-compartment contents of your pack dry.
I started my illustrious hiking career with a bulky pack cover that did a very good job collecting water in the bottom, soaking through the bottom of my pack. After a few trips, I switched to a trash compactor bag liner. These days, there are plenty of pack liner options. Liners can be as simple as a trash compactor bag, a clear plastic liner made for backpacking, or a fancier roll-top stuff sack. Pack liners also serve double duty to keep your wet items separated from your dry items. Did your tent get soaked overnight? When you’re packing up, leave your dry items in the pack liner, roll it shut, and throw your gross tent on top of the liner.
I tested a variety of pack liners over the past month. They all did their job keeping my gear dry, and were similarly easy to use. The main differences are in closure, materials, and price point. Here are the details.
MSRP: $2.24 for one (available in packs of 1, 2, or 3)
Size: Fits up to a 70-liter pack (20” x 36”)
Weight: 0.9 ounces
Pros: Extremely inexpensive, ultralight, durable. More structured bottom than some of the other plastic-bag styles. You can trim this bag to fit your smaller pack.
Cons: There’s no securing the top—you’re rolling and twisting like you would a trash compactor bag; won’t last as long as DCF or SilNylon.
I’ve never heard of this Nylofume before, and had to look up whether it was a material, brand, or smartly marketed combination of the two. After some internet digging, I’m still not quite sure. I did find out that nylofume bags are made of nylon polymer, and used to help protect food during fumigation. Lucky for the gram-and-dollar weenies out there, these are also for sale as pack liners. The bag I tested works splendidly in my 60L pack, and also fits in a pack up to 70 liters. In the end, I trimmed it to fit in my 45L bag (pictured), which is what I usually carry. This liner was totally waterproof once I did my usual twist-and-roll, and ended up feeling more durable than a trash compactor bag.
Size: 50L, 70L, 90L
Weight: 2.6 ounces
Materials: 30D Ultra-Sil CORDURA
Pros: Multiple levels of closure for waterproofing, can be used to carry and store items when not used as a pack liner. It also has increased durability over the “plastic bag” models.
Cons: There are less expensive options out there; weighs more than others on this list
Usage: This feels like one of the most protected liners on this list. I’ve used Sea to Summit dry bags and stuff sacks for years, and this one uses a similar roll-top / buckle closure. It stands out from others on the list thanks to a two-step closure. Two hook-and-loop tabs fold in to close the bag, then you roll the top closed and buckle it to complete the process. I have the 70L (pictured) which is almost comically large for my 45L pack. This liner comes in three sizes, so be sure to get the one that fits your bag the best. This liner’s finish made it easy to pull in and out of my bag, even when it was crammed full.
MSRP: $100 for 2-pack (one small and one large)
Size: 40L, 60L
Weight: 2.2 ounces
Materials: Dyneema Composite Fabric (DCF)
Pros: Lightweight, ultra-durable, snug fit, wide opening for gear
Cons: The obvious downside is the price of this liner compared to literally everything else on this list.
This is the only DCF liner on this list, and it’s the first one I tested. DCF is the gold standard for ultralight, durable, waterproof outdoor gear, and this liner is no exception. If you’re willing to spring for it, opting for a DCF bag is never a bad splurge. These bags have structured bottoms, fit smoothly into a pack, and have a secure roll-top closure with a buckle. Like the Sea to Summit liner, I’ve been storing gear in this liner when I’m not using it for backpacking. The buckles are lightweight and small, but easy to use with cold fingers, and I was able to get at least two rolls of the roll-top closure even with a pretty full gear haul.
Mountain Laurel Designs also sells a pack liner bag for $5, which is your very basic clear plastic bag.
MSRP: $5 (pack of 2)
Weight: 1.2 ounces|
Materials: Polyethylene film
Pros: Extremely inexpensive, simple, fits small packs best (35-50L)
Cons: One of the less durable on this list; felt somewhat small for my gear. Would have liked to be able to roll the top more.
These clear liners are great for one long trip, but I don’t know if they’d last much longer than that. I’d recommend these for people with smaller pack sizes, as I didn’t feel like I was able to get enough “rolls” in the opening and tuck it under for total waterproofing. It kept my gear dry in moderate rain, but I don’t know if I’d trust it with total pack saturation. For reference, I have a 45L pack. If you’re going to get a clear plastic bag liner, the Nylofume is a larger, somewhat more sturdy option for the same price.
MSRP: $11 for pack of 5
Size: 18 gallons (68L)
Weight: 1.4 ounces
Pros: Can be found at almost any generic store, inexpensive, durable, large capacity
Cons: Comes in packs of 5-10, so you’ll have to find people to share with
This is the OG hiker trash waterproof pack liner. The standard size fits an 18-gallon trash can, which translates to fitting a 68L pack. My trash compactor bag lasted over 1,000 miles of wet hiking, and had plenty of capacity to roll it down multiple times to keep my gear protected. If you’re going this route, be sure to get the compactor bag and not a regular trash bag. Trash compactor bags are different than standard trash bags in that they are far more durable, and have wide mouths instead of drawstrings.