In France, the estimated number of new cases of Chronic Lymphocytic Leukemia/Lymphoma (CLL/LL) in 2018 was 4,674, including 2,770 cases in men and 1,904 cases in women. Key points: Favorable prognosis with a 5-year standardized net survival rate of 89% for individuals diagnosed between 2010 and 2015; Individuals aged 80 die more frequently from causes other than their CLL/LL (observed survival of 63% and net survival of 82% at 5 years); Improved 5-year net survival regardless of age at diagnosis between cases diagnosed in 1990 and those diagnosed in 2015 (+16 percentage points): Less marked improvement after 2005 (difference between 2015 and 2005 in standardized net survival of +6 percentage points). : Excess mortality is virtually zero for people under 80 years of age starting in the first year of follow-up.