Fastpacks 15L–40L Australia

How to Choose a Fastpack for Trail Running or Fastpacking

A fastpacking pack is not the same thing as a daypack. Fastpacks are purpose-built for moving fast with an overnight kit like a sleeping bag, shelter and food, packed into a slim, lightweight body that does not swing, bounce or restrict your movement on trail. If you are looking for a general-purpose day hiking pack, our daypacks under 30L collection is the better starting point. 

But if you are heading out for one or more nights and speed matters, you are in the right place.

What is the Difference Between a Fastpack and a Daypack?

The functional difference is overnight capability. A fastpack in the 25L–40L range is specifically shaped and structured to carry a compressed sleeping bag, a lightweight shelter and a stove without the pack ballooning out or pulling awkwardly on your shoulders. Fastpacks also typically run frameless or with minimal structure, aka weight savings that matter when you are running or moving at pace for hours at a time.

A daypack in the same volume range carries more comfortably for a single day but is not designed to compress a sleeping system or manage an overnight food carry efficiently.

What Volume Do You Need for a Fastpacking Trip?

The calculation is straightforward: one night out needs at minimum 20–25L if your sleep kit is properly ultralight. Two nights needs 30–35L. Three or more nights pushes you toward 38–40L or into dedicated ultralight pack territory; see our ultralight multi-day hiking packs for that.

At the lighter end of this collection, the OMM Ultra 20 and Gossamer Gear Minimalist 19 sit below 20L; suited to experienced fastpackers with a dialled, sub-3kg sleep system. For most people, 28–36L hits the sweet spot for one to two nights without sacrificing pace.

Which Brands Make the Best Fastpacks?

For race pedigree: OMM (Original Mountain Marathon) designs packs for mountain running competitions. The Classic 25 is used in events across the UK and Europe and is one of the most tested fastpacks in any weather condition.

For raw weight: Gossamer Gear and Hyperlite Mountain Gear lead the field. The Fast Kumo 36 and the HMG Aero 28 use ultralight fabrics that shave meaningful grams without losing structural integrity under load.

For ease of use and a great fit straight out of the box: Durston Gear's Wapta 30 is a strong all-rounder. It’s well-priced, well-made, and available in Australia through Ultralight Gear when you cannot find it elsewhere.

Staff Picks: What Our Team Reaches for When Moving Fast

For a single fast night out, the Gossamer Gear Fast Kumo 36 is our pick. It sits under 400g, takes a full sleep kit at pace, and carries without shifting on technical terrain. For pure trail running with overnight kit, the HMG Aero 28 carries everything you need for a night out and does not feel like a pack when you are moving.

Unsure which fastpack suits your pace and overnight plan? 

Come into the Ultralight Gear store in Alexandria and try one on loaded. Our team uses this gear on trail and can help you spec your kit from scratch. We also price-match if you saw it cheaper somewhere else; ask for a deal.

Browse related collections: pack accessories for lightweight add-ons, or waist packs and hip belts if you want to carry even less on shorter efforts.

Frequently Asked Questions

What is fastpacking exactly?

Fastpacking is trail running or fast hiking with an overnight kit. It sits between trail running (day only) and backpacking (slower, heavier). The goal is to cover more ground per day than a traditional hiker by running or moving at pace, while carrying a minimal shelter, sleeping bag and food for one or more nights.

Can I use a trail running vest instead of a fastpack?

For a single light night out with an ultralight sleep kit, yes. Some experienced fastpackers manage a one-night carry in a well-packed 15L vest. For two or more nights, or if your sleep system is not yet dialled below 1kg, a 25L–40L fastpack gives you the volume and organisation to carry food, water and shelter without compromising your movement on trail.

How do I fit a sleeping bag into a 30l fastpack?

Use a compression sack or waterproof stuff sack to compress your sleeping bag before packing. An ultralight quilt or synthetic bag compresses smaller than a traditional sleeping bag. Aim for the sleeping bag to occupy no more than 8–10L of your pack's volume. This leaves room for shelter, food, clothing and a water carry in a 30L fastpack for a single overnight.

Are frameless fastpacks comfortable for heavy loads?

Frameless packs, like those from Gossamer Gear and Pa'lante, carry best when your total pack weight sits below 10kg. Above that, a frameless design starts to feel unsteady because there is nothing to transfer load to your hips. If your overnight kit is genuinely lightweight (sub-6kg loaded), frameless is fast and comfortable. If you are still refining your kit, consider a semi-structured pack like the Durston Wapta 30 while you dial your base weight down.

What is the lightest fastpack available in Australia?

From this collection, the OMM Ultra 20 and the Gossamer Gear Minimalist 19 sit among the lightest options available locally. Both come in under 250g. The HMG Aero 28 in DCF fabric is another benchmark at around 320g. These weights are for the pack only. Each gram saved on the pack is a gram you can allocate to a better sleep system or more food.

Do I need trekking poles with a fastpack?

Not necessarily, but many fastpackers use them for descents and to pitch trekking pole shelters. Several fastpacks in this collection, including the Pa'lante and Gossamer Gear range, have lash points or side pockets designed to stow poles while you run flats and climbs, then retrieve them on technical descents. If you already use trekking poles, check the pole attachment setup before you buy.