FOX UNION CLIPLESS BOA SHOE REVIEW

July 28, 2026

The Loam Wolf crew has spent good time in the Fox Union BOA clipless shoes over the last few years, as the dedicated shoe of our eMTB Shootouts, and a shoe that many have continued to run on the daily. That said, they were not a shoe with unanimous praise, suffering from a few drawbacks.

We wanted to get the opinion of one of our audience to add to the collective Loam Wolf narrative on Fox’s top-tier clipless mountain bike shoes, so were stoked when member Jody – who made a brief appearance in our 2026 eMTB Shootout – shared his thoughts with us for this review.

ABOUT THE FOX UNION BOA CLIPLESS SHOES

The Fox Union shoes are now in their second iteration, having originally launched in 2023. For Gen 2, Fox updated the Union line of shoes with an all-new upper which features a blend of materials. With the use of a TPU-welded upper with ripstop material, Fox aimed to bolster the durability of the Union shoe without sacrificing comfort. The construction and the fit have also seen some updates, for better and for worse. Fox also partnered with D3O to add a little extra cushion to the outsole, taking the sting out of the trail.

An item that hasn’t changed on the Union BOA Clipless shoes are the use of a dual-dial Li2 Fit system from BOA. The BOA Fit system is great for making on-the-fly micro-adjustments, speeding up the time it takes to put the shoes on and take them off. On the topic of adjustability, all Fox Union shoes come with two sizes of arch supports, which can be easily swapped to tailor the fit to the rider’s foot. Fox continues to use a reinforced toe box for protection against rock strikes. Off-bike grip is made possible thanks to the Ultratac rubber compound and a hexagonal tread pattern. Being a clipless shoe, the Fox Union Clipless shoe uses a cleat-bed compatible with all 2-bolt cleat systems. The cleat bed itself has a lined texture to help with cleat grip, along with markings signifying a power or control setup. Between the foot and pedal, a molded internal stiffening plate is in place to boost power transfer.

The Fox Union BOA Clipless shoes have an MSRP starting at $274.95 / £219.99, in sizes ranging from 37 to 47, and with 7 standard color options. Depending on when you are looking, there may even be a handful of limited edition colorways available. If dual BOA is not your thing, Fox offers the Union shoes with a lace closure, and a BOA and Power strap combo. If you aren’t a clipless rider, flat pedal options are also available in most configurations.

TESTING THE FOX UNION BOA CLIPLESS SHOES

FIRST IMPRESSIONS

The Fox Union Clipless BOA feels like a well-made premium shoe, with a wide, protected toe box, D3O insoles, and removable arch support. Out of the box, the Unions are true to size (size 47 tested) with zero heel lift and confidence-inspiring protection. They are very stiff shoes, and I did initially experience hot spots and a long break-in period. Those have now gone away, and I don’t think twice about wearing them for all-day missions out on the bike.

CLEAT SETUP AND PEDAL COMPATIBILITY

I’ve now been riding the Fox Union Clipless BOA since the end of April and have put approximately 700 miles on them. The updated Union still takes some finessing with the Mallet E pedals; however, this could be down to my giant size 13 feet. After taking advice from other riders and adding an extra shim, I managed to make them feel more consistent both when clipping in and when releasing. The cleat channel does feel rather deep, so even with the extra spacing from the shims, I can still walk around without feeling like I am skating on ice, or sounding like a tap dancer.

I have since upgraded from Crankbrothers Mallet E pedals to Mallet DH, and the experience with them is very different. The connection is consistent, and the cleat release feels intuitive and predictable, which is exactly what I look for in a shoe-pedal combo. To the point where I have added a little more pedal pin grip, which is great for those emergency situations when you don’t have time to get back into the pedals. The grip on the Union BOA sole has been great for this, making you feel as secure as you can on a set of clipless pedals over short sections of chunky trails.

THE ELEPHANT IN THE ROOM

Personally, I’m a big fan of the BOA closure: the simplicity, speed, ability to fine-tune, and the fact that I’m usually too lazy at the end of a ride to undo my laces mean I get along with them well. I’ve run BOA on many different shoes in the past and many a time been warned about when they go ‘pop’, but I’ve never had an issue. Well, this changed with the Fox Union BOAs. Early on, on a 2000m descent in the Swiss Alps, I was unfortunate enough to clip a rock and suddenly felt my shoe was loose. Hoping I had just dislodged the dial and released them, I realized I had snapped one of the cables.

SO WHAT NOW?

Well, the great thing about the cables on the Fox Unions is that they use BOA CS2 laces, a thin, nylon-coated stainless-steel wire that enabled me to tie them back together and get back to riding without a second thought. After snapping them, I continued to ride with them tied for the rest of my trip with no issues.

LONG-TERM PERFORMANCE

Having ridden these for three months, I’ve been very happy with the Union BOAs overall. Breathability is on par with similarly made competitors’ shoes, and personally, I am happy to take a bit more protection over ventilation. The combination of the stiffer sole and the vibration damping of the D30 insoles makes a noticeable difference in both power delivery on climbs and fatigue on long descents. I put these shoes through their paces on both my home trails in the Tahoe region, and on my latest trip in the Swiss Alps, racking up over 75000’ of descent in one week. The main drawback I found with the stiffness was when it came to hike-a-bike; in one case, I suffered with some tasty blisters and Achilles strain when hiking up a 1000’ climb. So, if regular hike-a-bike is your thing, then that might be something to take into consideration.

VALUE

The Union BOA comes in at $275, which, for me, is definitely on the upper end of what I would consider paying for a pair of shoes. At the same time, they are holding up better than my previous set of Crankbrothers Mallet DH Shoes. So, even if the initial cost is a little harder to swallow, they are an extremely well-made and robust pair of shoes that so far look like they should last me at least a couple of seasons. There are also lace-up versions that offer better value without sacrificing much performance, or the single Boa and power strap combo which could offer the best of both worlds.

The Wolf’s Last Word

The Fox Union BOA is a great shoe for aggressive trail, enduro, and DH riders who prioritize protection and support over walkability. This shoe is better suited to average-to-wider feet with its visually wider toe box, while still offering plenty of security and support in the heel for narrower heels.

Price:  $274.95  / £219.99
Website: Foxracing.com

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