You can open carry in Utah with or without any state permit. The only difference is this...
With a permit, there are no restrictions on how you carry.
Without a permit in Utah, the firearm must be unloaded, meaning no chambered round, but a full mag in the weapon is OK. And avoid school zones.
76-10-502. When weapon deemed loaded.
(1) For the purpose of this chapter, any pistol, revolver, shotgun, rifle, or other weapon described in this part shall be deemed to be loaded when there is an unexpended cartridge, shell, or projectile in the firing position.
(2) Pistols and revolvers shall also be deemed to be loaded when an unexpended cartridge, shell, or projectile is in a position whereby the manual operation of any mechanism once would cause the unexpended cartridge, shell, or projectile to be fired.
(3) A muzzle loading firearm shall be deemed to be loaded when it is capped or primed and has a powder charge and ball or shot in the barrel or cylinders.