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Advice on sizing for La Sportiva hiking boots

Hi,  I am interested in the GTX line of La Sportiva hiking boots. Their sizing seems to run small. I have a size 12 foot and have 2 pairs of la sportiva shoes in size 47. But I also own a pair of la sportiva mids that are a size 46.5. Your advice based on your experience??


3 Replies

Hi there @Mar !

Fitting boots can be tricky! As you mentioned, sizing can fluctuate, not only from brand to brand but even between styles of the same brand. With that being said, I own this pair of La Sportiva’s and they are one half size larger than other shoes I wear. 

While shopping in our stores is not an option yet, we do have employees offering free virtual outfitting appointments, which could prove helpful in making this decision. 

I’ll also tag some of our footwear experts here in case they would like to add to the conversation! @REI-PearlD @REI-CharityP 

Hope this helps!

At REI, we believe time outside is fundamental to a life well lived.

Hi @Mar

La Sportiva sizing can be a bit tricky, as the shoes are constructed on a last that's based on European sizing, which doesn't exactly correspond to US sizes.

The term "GTX" indicates that the boot has Gore-Tex, or a waterproof layer. Many La Sportiva boots have Gore-Tex, so it would be helpful to know the models of boots you're considering such as the La Sportiva Nucleo or the La Sportiva Saber. 

Generally, we recommend that you have at least a thumbnail's width (side to side measurement) of room in the toebox from the end of your longest toe to the end of the shoe. Depending on the thickness of your socks, you may need more room. Therefore, I'd likely recommend choosing the 47. 

If the 47 ends up being too long, you have some options:

-Wear thicker socks to fill the volume of the boot, or

-Use an after-market insole to fill the overall volume of the boot, or

-Take advantage of our 100% Satisfaction Guarantee to reorder the boots in a smaller/larger size.

I hope this gets you started. Let us know which boots you're considering and we can explore sizing a bit more!


At REI, we believe time outside is fundamental to a life well lived.

Hi @Mar !  

I am not an REI employee, but I just purchased a pair of La Sportiva Nucleo online, the men's version of the same boot @REI-AlyS has.  And I completely concur with both her and @REI-PearlD.  Go at least 1/2 size larger in the corresponding US size, possibly 1 full size.  I typically wear a size 9 US, and got a 42.5 (9-1/2 US), and they fit nearly perfectly right out of the box, just a bit snug.  I've worn them around the house and so far, in just that short time, they've become much more comfortable. I'm sure these will work out fine for me, although I was hoping for a slightly looser fit to accommodate thick socks, but I don't think that's in the cards. 

Good luck!

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