Ortlieb Seat-Pack review: a bombproof piece of bikepacking kit

Ortlieb has an epic reputation for being the pinnacle of bike bag design and its latest Seat Pack shows why

Ortlieb Seat Pack
(Image: © Guy Kesteven)

BikePerfect Verdict

Expensive, but that’s an investment in a benchmark re-setting, expedition-quality bag that’s going to be a secure, stable, totally waterproof, and versatile bikepacking essential for a very long time.


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    Totally waterproof

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    Legendarily bombproof

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    Stable and secure on the bike

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    External cargo bungee

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    Light mounts and reflective patches


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    Initial investment cost

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    10-15 percent heavier than lightweight bags

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Hartmut Ortlieb handmade his first bike bags after a sodden touring trip around Britain where he realized that the only thing staying dry on the roads was the cargo hidden under heavyweight tarpaulins on trucks. Fast forward just over 40 years, and the brand’s reputation as the go-to bag for bombproof weatherproofing is stronger than ever, but it’s fair to say it’s been obscured by the massive explosion of options from other brands vying for a claim to the best bikepacking bags crown. Ortlieb’s new Seat-Pack does a brilliant job of re-establishing the brand’s rightful position at the top for those prepared to invest in the best. Read on to find out what makes it so good.

Design and aesthetics

The Ortlieb Seat-Pack comes in the 11L version I tested, and a 16.5L option which is basically the same, but costs $10 / £10 more and has two seat post straps and an extra ‘X’ on the crossover bungee. The main bag is a tapered cone of totally waterproof, hexagonal Ripstop-reinforced PVC-free ‘PS21R’ material. This is joined with a welded seam along the base that zig-zags around an extra panel of ‘daisy chain’ loops that can be used for a clip-on rear light. 

The front of the bag is further reinforced with a wrap of even tougher material that also folds up to provide the triangular wings that the plasticky/rubbery saddle straps anchor onto. The fabric is doubled over behind the heavy-duty seat post strap that wraps back through an alloy buckle and is secured with ‘hook and loop’ panels on both the strap and the side of the bag. 

The front section also has a stiff plastic internal liner around the front and sides to stabilize the bag and stop it from bulging out into your legs. This provides the mounting plate for the front strap and the saddle rail straps to bolt into. And yes, I said bolt, not stitch or glue, because in the very unlikely event of them getting snapped or frayed, Ortlieb makes it easy to replace them. 

The saddle straps also use seriously tenacious strap locks, so there’s no danger of them loosening, even when fully loaded. The iconic Ortlieb roll-top seal design (it has an equally legendary reputation for its waterproof haul bags among climbers, cavers, and mountaineers, and it also makes custom bags for mountain rescue teams) means you can also roll the bag down from the full 11 liters down to 7 liters. 

The side straps that cinch it down have Velcro straps to tidy up loose ends and there’s a crossed cord-locked elastic on the top for quick-grab items like spare layers, etc. Four reflective panels enhance visibility whatever size you roll it to, and there’s even a release valve on the side so you can expel air and get the most compact pack possible.


If the fact you only need to pull an air valve to pack it down isn’t proof enough that this is a totally waterproof pack (Ortlieb gives it an IP64 rating) I’ve ridden with it in filthy conditions and hosed it down afterwards repeatedly without a hint of moisture getting inside. Obviously you can keep stuff dry even in a leaky pack by using plastic bags inside, but knowing that you won’t ever find your spare clothes sopping when you put them on creates a warm and fuzzy feeling all of its own.  

After a couple of months of use, I've not had any wear, and speaking to long-term Ortlieb users I’m not likely to see any for a very long time yet. That’s a welcome contrast to other bags where I've had corners and friction spots hole through after just a few hundred miles.

The stiffened nose with rigid mounting straps and locked-down buckles mean it’s super secure and bounce-free on the bike, but only takes a couple of seconds to take off. It’s also impressively stable, even when climbing out of the saddle with it stuffed. 

The more structured build means it only needs 6cm of exposed seat post to mount (the 16.5L bag needs 15cm) and the high ride height means it works well on small frames, suspension bikes or just if you want some post space free for a rear light. I did have a slight issue with a kinked Thomson seat post pulling the bag further under the saddle than normal, so the bungee partly disappeared under the seat, but that’s a very niche complaint. 

Considering the bolted mounts and generally bombproof build of the bag, it’s much lighter than you’d think at 360g too, which is within 10-15 percent of far flimsier bags I've used.


Saddle bags have a tough job. Doing their best not to swing or get worn out rubbing around under your saddle as you rattle along rough trails, while stopping rear wheel spray and weather doing its best to sneak into your cargo and ruining your adventure, isn’t easy. 

Out of all the bags I’ve used since I got my first canvas and leather Carradice 40 years ago (suck on that, hipsters) Ortlieb’s new Seat-Pack is without doubt the best I’ve used for bombproof, guaranteed waterproof and generally bother-free cargo carrying. 

Unless you’re just looking for an occasional or one-off use bag, the high initial investment is a totally fair price to pay for the life you’re going to get from Hartmut’s latest handiwork.

Tech Specs: Ortlieb Seat-Pack

  • Ortlieb Seat-Pack 11L
    • Price: $180 / £135
    • Size: 40 x 26 x 15cm 
    • Weight: 360g 
    • Colors: Black
  • Ortlieb Seat-Pack 16.5L
    • Price: $170 / £145
    • Size: 64 x 30 x 22cm
    • Weight: 460g 
    • Colors: Black
Guy Kesteven

Guy has been working on Bike Perfect since we launched in 2019. Hatched in Yorkshire he's been hardened by riding round it in all weathers since he was a kid. He spent a few years working in bike shops and warehouses before starting writing and testing for bike mags in 1996. Since then he’s written several million words about several thousand test bikes and a ridiculous amount of riding gear. To make sure he rarely sleeps and to fund his custom tandem habit, he’s also penned a handful of bike-related books and talks to a GoPro for YouTube, too.

Current rides: Cervelo ZFS-5, Forbidden Druid V2, Specialized Chisel, custom Nicolai enduro tandem, Landescape/Swallow custom gravel tandem

Height: 180cm

Weight: 69kg