A filter housing of a fluid filter has a housing body with inlet and outlet openings for fluid. The housing body has an element receptacle for a filter element that separates inlet opening from outlet opening. The housing body has an installation opening providing access to the element receptacle in an installation direction and enabling insertion of the filter element into the element receptacle. The installation opening is arranged at a transverse side of the housing body laterally relative to a housing axis that is transverse to the installation direction. A housing cover closes off the installation opening. The housing body has a sealing surface contacting a seal of the filter element when inserted in the element receptacle and surrounding the housing axis at least partially circumferentially. A fall-out protection device prevents the filter element from falling out of the element receptacle when the installation opening is open.