Generally accepted assumptions about fertility, mortality and migration suggest that between 61 and 79 million people will live in mainland France in 2050. In the general scenario, which supposes that recent demographic trends will continue, 70 million people will live in France in 2050, i.e. 9.3 million more than in 2005. The population will rise throughout the whole of the projected period, but at an increasingly slow rate. As the population ages, the number of deaths will increase sharply and will exceed the number of births around 2045. Introducing the migratory balance of 100,000 net entries per year into the projection would compensate for the natural deficit, thus bringing about demographic growth. In 2050, nearly one inhabitant in three will be over 60, compared with one in five in 2005. The proportions of young people and working-age people will decrease. On 1st January 2050, France will then have seven inhabitants aged 60 or over for every ten inhabitants aged between 20 and 59: this ratio will have almost doubled in 45 years. These results are in line with the accepted assumptions, but there is no scenario which challenges the idea that the population in mainland France will age between now and 2050, though the ageing of the population will remain less pronounced than in most European countries.