Background and Aims: The Covid-19 pandemic had a major impact on healthcare systems, challenging the continuity of chronic disease management. Patients with Chronic Kidney Disease (CKD) were identified as particularly at risk. The aim of this study was to measure the impact of the Covid-19 pandemic on their mortality using the French National Health Data System (SNDS). Method: The SNDS contains the outpatient and inpatient care of all the French population. We applied an algorithm to identify individuals with CKD based on the healthcare consumption available in the SNDS. We identified two cohorts: individuals identified with CKD in 2016 and in 2019. These two cohorts were followed for one year after the year of identification. Patients’ characteristics were extracted from the SNDS and compared between the two cohorts. The event of interest was death documented in the SNDS with death certificates. The follow-up year was divided into periods according to the chronology of the epidemic: pre-epidemic, first lockdown, post-lockdown and second lockdown. Results: The 2016 and 2019 cohorts included 570,701 and 674,008 individuals respectively. The two cohorts didn't differ in terms of age and sex or comorbidities (median age = 76 years old, 51% female). At 31/12 of the year following identification, 10.90% (n = 62,234) of the 2016 cohort had died, compared with 10.94% (n = 76,756) of the 2019 cohort. Among the 60-year-old and less, mortality in the 2019 cohort was lower than the mortality in the 2016 cohort in all periods of the follow-up year. This remained true among those aged ≥60 years old during the pre-epidemic period (Week 1-Week 10). During the first week of the first lockdown, the instantaneous risk of death for the 2019 cohort reached 5.42 individuals per 1000 in the ≥75-year-old group, compared with 3.12 in the equivalent period for the 2016 cohort (+68%). Conclusion: All results suggest overall lower mortality in the 2019 cohort of CKD. However, an increase in mortality was observed during strong epidemic periods in the age group of those over 75. These results will be completed with the analyses of the healthcare consumption in the two cohorts describe above.