Rationale & ObjectiveIn 2021, the new Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) updated the creatinine-based estimated glomerular filtration rate (eGFR) equation and removed the coefficient for race. The development and validation of this equation involved binarizing race into Black and non-Black, involving few Asian participants. This study aimed to examine the difference between the 2021 equation and the previous 2009 equation on CKD prevalence estimates in two Asian populations. Study DesignObservational study utilizing two national surveys. Setting & ParticipantsParticipants from the 2019 Korea National Health and Nutrition Survey and participants self-reported as Asian from the 2011-2020 United States (US) National Health and Nutrition Survey. ExposureeGFR using 2009 and 2021 CKD-EPI creatinine equation. OutcomesPrevalence of CKD (eGFR <60 mL/min/1.73 m2 or urine albumin-to-creatinine ratio [UACR] ≥30 mg/g) Analytical ApproachSampling-weighted prevalence estimated by the 2009 and 2021 equations as well as the percentage individuals with CKD G3+ by the 2009 equation being reclassified as not having CKD G3+ by the 2021 equation. ResultsThe prevalence of CKD estimated by the 2021 equation was 9.75% (95% confidence interval [CI] 8.80–10.80%) in Koreans and 11.60% (95% CI 10.23–13.13%) in US Asians. The prevalence of CKD estimated by the 2021 equation was slightly lower compared that by the 2009 equation in both Korean and US Asian populations, by 0.63% (95% CI 0.44–0.90%) and 0.84% (95% CI 0.52–1.34%), respectively. Further, 32.8% and 30.2% of Koreans and US Asians with CKD G3-5, respectively, by the 2009 equation were reclassified as not having CKD G3-5 when the eGFR was calculated by the 2021 equation. LimitationsMeasured GFR was not available. ConclusionsThe 2021 CKD-EPI creatinine equation led to a small decrease in CKD prevalence in both Korean and US Asian populations, and of similar magnitude, resulting in significant reclassification among those originally classified as having CKD G3+.