Ultralight Pack Liners (Backpack Liner)

The waterproof upgrade your expensive sleeping bag/quilt deserves

Most backpackers use a trash compactor bag or nylofume bags to keep their gear dry. It works… until it doesn't. Trash bags or other thin plastic bags rip and tear over time, leak after a few weeks, fall apart in your pack, and turn into trash you have to pack out.

Our Ultralight Pack Liner solves that, for the same trip count you'd cycle through 10+ trash bags, you get one liner that keeps going for years.

Made in our shop in Waynesburg, PA from Challenge D50T fabric.

the same waterproof material we use for our food bags and dry bags. Hand-built, taped seams, built to outlast your backpack.

Trash bag vs. Hilltop Pack Liner

Why ultralight hikers upgrade

• Waterproof Challenge D50T fabric with fully taped seams, no leaks, no patching with duct tape on trail
  
• Outer abrasion layer, protects against tent poles, stakes, and rough gear rubbing through
  
• Lighter than a Dyneema 2.92 oz liner, at a fraction of the cost
  
• Trusted by thru-hikers, on the AT, PCT, CDT, and beyond
  
• Backed by our 5-year warranty, if it fails on trail, we fix it.

Pick the right size for your pack

Lay your backpack flat. Measure the width. You want your liner just slightly wider than your pack. Don't worry about height, your tent and other non-critical items live below the liner anyway.

Small - 16.25" × 31.5" flat · 2.8 oz · For 20–33 L packs
Medium - 18.25" × 33.25" flat · 3.25 oz · For 35–50 L packs
Large - 21" × 35.25" flat · 3.85 oz · For 50–70 L packs

Not sure which size? Contact us, we'll figure it out together.

Frequently asked questions

• Do I really need a pack liner if my pack is "waterproof"?
  Most backpacks are water-resistant, not waterproof. Sustained rain, river crossings, and condensation will soak through eventually. A pack liner is the difference between dry sleep and a miserable night.
• Trash compactor bag vs Pack liner - what's the real difference?
  Trash bags work in a pinch. They rip on rough gear, leak after a few weeks, and you'll cycle through them constantly. A Hilltop Pack Liner pays for itself within a season of regular backpacking - and lasts years.
• Will this fit inside my backpack?
  Use the volume guide above. The liner is meant to be slightly larger than your pack interior so you can roll the top closed. If you're between sizes, go larger.
• How do I close it?
  Roll the top 3–5 times and clip or just tuck. The taped seams keep water out from the bottom and sides; rolling the top creates a waterproof seal.
• What if it fails?
  5-year warranty. If a seam fails or fabric tears under normal use, we fix it free.

Where is it made?

• In our shop in Waynesburg, Pennsylvania. Every liner is hand-built by our team - same crew that makes our backpacks and food bags.

Want to learn more?

• Read about Challenge D50T fabric vs Dyneema vs DTRS75
• Or see our full guide: Pack Liner vs Pack Cover - Which One Actually Keeps Your Gear Dry?

What is our Pro+ Line? Products with high-value technical fabrics like Ecopak, Xpac, and D50T. Pro performance at a friendlier price. More info on our 3 tierd approach to Ultralight Performance here.