Fluid pump having an internal bearing collar and method for assembling the fluid pump

An electric fluid pump may include a pump housing and an electric motor. A rotor may have a rotor shaft and may be mounted in a rotatable manner in a stator body, which may have a stator embedded at least regionally therein. The pump housing may be subdivided into a dry and a wet region containing the rotor. The rotor shaft may be mounted on a bottom side and may be connected to a pump impeller on a pump-impeller side, facing away from the bottom side. The pump housing may have, on the pump-impeller side, an aperture out of which the rotor shaft may project. The pump housing may have an internal first bearing collar arranged around the aperture, the dry region located radially around the first bearing collar, and an outside diameter of the first bearing collar being less than a maximum diameter of the rotor.