The Force was originally designed for a single mission, and there were no contingency plans in place to provide additional soldiers to replace fallen and injured Forcemen. During the Majo campaign in January of 1944, the American military authorized the Force to recruit new members. These first American replacements were trained in Force methods at its headquarters in Santa Maria. There were authorities from both countries who thought the FSSF should be disbanded because the problematic administration of men from two different armies was a constant challenge, and because it was difficult to bring replacements up to Force standards. Letters from Frederick and Lt. Col. T. Gilday (the acting senior Canadian officer) to their respective superiors indicate they were both in favour of ending the Force. However, the urgency to send reinforcements to the Anzio beachhead suspended the disbandment discussion, and the Force was redeployed to that theatre. The Canadian government then agreed to provide replacements as well.

    The majority of Anzio replacements were originally American Rangers. This unit, which had training similar to that of the Force, was amalgamated with the Force after the First and Third Ranger Battalions were decimated at Cisterna. The subject of the Force disbandment was raised for a second time after the Anzio-Rome campaign, but both countries agreed to keep it intact for the southern France invasion.

    In the fall of 1944, the war strategy in the European theatre was based on large scale infantry attacks, and Allied authorities saw little need for a small elite mountain force. In October, Force disbandment discussions were resumed.
    The FSSF commanding officer Col. Edwin Walker did his best to lobby for the retention of the Force, but to no avail. Orders were issued in November to deactivate the Force, and send its remaining members to other units

    On December 5, the Force gathered for a parade in a Villeneuve-Loubet field, and the announcement of the disbandment was made. Although the officers had prior notification, the enlisted men did not know the end was at hand. Following a memorial service for fallen Forcemen, the Canadian echelon was ordered to fall out, and they marched off the field. In a show of solidarity, the U.S. echelon then ignored the order to close ranks and left open the spaces vacated by their Canadian brothers.

    At deactivation, there were 620 Canadians members, and they were sent back to Italy. From there, the men that were qualified paratroopers were transported by sea to the U.K. to be used as instructors or incorporated into the First Canadian Parachute Battalion. The others were redeployed to various Canadian units in Italy.

    Of the 1471 American Forcemen, 353 were reassigned to the 82nd Airborne Division and 101st Airborne Division while the remainder joined the newly formed 474th Infantry Regiment under the command of Col. Walker. The 474th Infantry Regiment participated in security details and was deployed to Norway after the surrender of Germany to facilitate the processing of German prisoners of war in that country.