That will depend on the boot model.
If you are thinking on buying snowboard boots online, don't do it!
Boots are the most important piece of gear and you need to try as many as you can physically.

 

It’s not easy to try boots here in Greece Vans infuse is the model

 

If your feet are 280mm I would say no. In my experience Vans (in my case Verse) boots are pretty true to size. My feet are about 268mm and I rode Verse US9/mondo27 and it was a snug performance fit. For Ride and bataleon i can downsize to us8,5 but not with Vans.

 

I usually wear an 11.5, but in my infuses I fit best in the 11.

 

I wear 10.5 in Vans Old Skool Shoes and wear a 10 in Infuse Boots

 

Thank you all for the reply’s unfortunately the vans infuse size us 9,5 doesn’t fit in 28 cm mondo