Big Agnes’ Lightest Sleeping Pad Yet: Zoom UL Review

I was at the Douglas Springs trailhead in Saguaro National Park, playing a final round of Tetris with the items in my pack before I got on the trail. Since water access was limited on my multiday hike, I had to start with 8 L of water, which added a lot of base weight and took up a ton of space in my bag.

When it came time to add my sleeping pad, the Big Agnes Zoom UL, I let out a thankful sigh of relief. The pad is just slightly bigger than a Nalgene bottle and weighs a scant 14 ounces. It slid right in alongside my cooking pot. Later that night, as I slept comfortably at a rocky, gravel campsite, I was once again thankful for the Zoom UL. 

Ultralight gear is often a game of tradeoffs. As the ounces go down, the price shoots up. But Big Agnes is challenging that principle with its Zoom UL Sleeping Pad. It’s the brand’s lightest-ever sleeping pad, and it comes at a price that’s hard to beat — especially in the world of ultralight gear.

After weeks of sleeping on the Zoom UL while backpacking and camping in Arizona, Utah, Illinois, Tennessee, and Arkansas, this pad has done more than enough to earn a space in my gear closet. While I would change a few things about the design, it’s hard to beat the weight and comfort for the price.

In short: The Zoom UL weighs just 14 ounces at its regular size (20×72”) and is priced lower ($179) than similar brands like Therm-a-Rest and Nemo. With an R-value of 4.3, this sleeping pad is plenty warm for most outdoor conditions while taking up little space in your pack. Ultralight backpackers and anyone who values lightweight, cost-effective gear will appreciate almost everything about the Big Agnes Zoom UL.

Review: Big Agnes Zoom UL Sleeping Pad

I tested the 25×72” size of the Zoom UL on multiday backpacking trips in Saguaro and Bryce Canyon national parks. I also slept on it while camping multiple weekends in Shawnee National Forest in southern Illinois. Conditions ranged from the high 70s to the low 20s, including a snowy night in Utah and several thunderstorms in Illinois.

The Zoom UL is Big Agnes’s lightest pad, making it a great fit for backpackers who count each ounce. The 20×72” pad weighs just 14 ounces, and the 25×72” version weighs 17 ounces.

For comparison, our best overall backpacking sleeping pad on our guide to the Best Backpacking Sleeping Pads, the Therm-a-Rest NeoAir XLite NXT, weighs 13 ounces at the 20×72” size.

During my trip to Bryce Canyon, I had to pack a bulky bear canister and many layers due to the cold. My bag was crammed full, so I was grateful that the Zoom UL packed down to such a compact size in its stuff sack.  

Sleeping on the Big Agnes Zoom UL Pad

My sleep setup consisted of the Zoom UL with a Mammut Siku Down -6F bag in the Marmot Limelight UL tent. Unlike the Big Agnes Campmeister and Boundary Deluxe pads, which have a slightly soft, felt-like material on the top of the pad, the Zoom UL is just nylon.

This surface was very slippery. Even on flat ground, my sleeping bag was constantly sliding and slipping around. This was also the case when I tried sleeping on it with my Nemo Disco 15 bag. 

On the positive side, the Zoom UL’s quilted design and O-beam construction cradled me comfortably. I felt no pain points or places where the ground or pad dug into my body. The pad is 3.5 inches thick on the outer chambers and 3.25 inches thick in the middle. That helps keep the user in the middle of the pad. 

On previous tests of other Big Agnes pads, I tested the 20×72” version and found it to be too small. That’s coming from someone who is only 5’6”. This time around, I tried the 25×72” for comparison. As someone who sleeps on their stomach and tosses and turns frequently during the night, I appreciated the extra 5 inches of width.

With an R-value of 4.3, the Zoom UL offers a great warmth-to-weight ratio. The only time I truly felt the cold of the ground was during one below-freezing night in Utah during a snowstorm. The Zoom UL makes for an excellent three-season pad. For winter use, I’d add another layer of protection like Nemo’s Switchback. 

After several months of regular use, the Zoom UL is still in great condition. So far, there is no visible wear or tear and no leaks. About 2 years ago, my previous Big Agnes pad, the Q-Core Deluxe, got a pretty large hole in it, so I am curious to see about the Zoom’s long-term durability. 

One Drawback: The Valve

Many of Big Agnes’s pads that I’ve tested (including the Rapide SL and the Q-Core Deluxe) have a dual valve. There’s one for inflation and one for deflation. The Zoom UL, however, has just one valve. To deflate, you stick a small tab on the valve cover into a tiny slot, which can be quite finicky. Compared to Big Agnes’ dual valve, this construction makes the pad far more difficult to deflate.

With the dual valve design, deflation was easy. You could lie on the pad with the valve open, and most of the air would go out. On the Zoom UL, I really had to squeeze and apply pressure to force air out. Deflating the pad every morning while backpacking was a chore.

When it comes to rolling up the pad to put it back in the stuff sack, you have to leave the tab in to get all the air out so it fits in the sack. But the valve cover sticking out also makes it more difficult to fit back inside the stuff sack. Even after packing up the pad multiple times, I still found the valve mechanism and packing up the pad to be cumbersome. 

A Note on Price

The 20×72” version of the Zoom UL retails for $179, and the 25×72” size retails for $230. I would purchase the larger width, even though that an extra 5 inches adds $50 to the price.

It’s still competitively priced, though. For reference, the 20×72” Therm-a-Rest NeoAir XLite NXT pad costs $209. The 20×72” Nemo Tensor Trail Ultralight Pad also costs $180, but the Zoom UL comes with a much higher R-value (4.3 compared to just 2.3). Sea to Summit’s 22×72” Ether Light XT Insulated pad costs $200 and has an R-value of just 3.2.

It’s hard to find a better lightweight, warm pad for the price than the Zoom UL.  

Big Agnes Zoom UL Sleeping Pad: Conclusions

If you’re looking for an ultralight backpacking pad that still delivers warmth, the Zoom UL is a great pick. However, the valve design and deflating process are tricky and time-consuming. It’s something to consider if you’ll constantly be packing up the pad on a long thru-hike. With the Zoom UL, Big Agnes has delivered its lightest pad to date without sacrificing comfort. 

The valve design and process of deflating the pad can be tricky and time-consuming. That’s something to consider if you’ll be packing up the pad daily on a long thru-hike.

If you’re a backpacker who tends to be active in the shoulder seasons or in colder places, the Big Agnes Zoom UL is a terrific option. It delivers an exceptional amount of warmth and insulation for its low weight. As a Midwesterner, it’s hard to imagine a scenario where the Zoom UL wouldn’t be adequate. The Zoom UL is a great choice for backpackers who count ounces but still prioritize getting good sleep on the trail.