When the Britannic was sunk in late 1916, the need for high-capacity hospital ships was even more dire, and she continued in this role until the United States entered the war in 1917, when she was deployed back to the Atlantic to ferry American troops to the continent with space for some 5,000. In 1918, her military service was cut short by an engine room explosion that killed nine crew members and thus required extensive repairs. Returned to the CGT in March 1919, her name was promptly changed back to France, although she was kept busy repatriating American troops until that autumn. She was sent for refurbishment that winter, returning to commercial duty in early 1920. In 1921, she passed flagship status on to the newer and larger Paris, but continued to be a popular means of travel, with a near club-like following among the wealthy. Her affluent passenger loads swayed the CGT in 1924 to convert her to an all first-class ship, save for just 150 third class berths. During the conversion, her boilers were modified to burn oil fuel rather than coal, allowing her engine room staff to be greatly reduced. She sailed without incident, crossing the Atlantic during the peak months and cruising in the winter until 1927. With the advent of the new Ile de France, France was diverted almost totally to cruising. The Great Depression essentially sounded the death knell for the liner. Many of the millionaires she had carried over the years had been financially destroyed and the general downturn in business cut deeply into transatlantic travel. The France spent more and more time idle, until she finally was withdrawn from service in 1932.
Laid up at Le Havre, she sat unattended until January 1933, when a fire was discovered by a night watchman. Although it was rapidly extinguished, the fire had caused some minor damage, but by now she was outclassed by her newer running-mates. CGT had by then commissioned a new flagship, the great Normandie which was nearing completion. As a result, the company decided it was time to scrap the 21-year-old liner. On 15 April 1935, the old France departed Le Havre under her own steam to the scrappers at Dunkirk, Scotland.