Check out our binding size chart here.
Mens Boot size US11/EUR44 is the magical number between binding size M and L, that means it always depends on the boot model. Some will fit OK into a medium others will require a large binding.
Bindings have lots of possible adjustments, gas pedal, ankle and toe straps, high back angles and rotation. In general it is better to have a binding be a little too snug than too big....So if in doubt, reach out.