The prevalence of chronic kidney disease (CKD) has been increasing worldwide. In practice, the glomerular filtration rate (GFR) can be assessed by the dosage of creatinine serum, its clearance through the kidneys and estimation formulae. However, there is no existing consensus about the best method of assessment; therefore, the aim of the present study is to assess the different methods of detecting CKD. A total of 293 hypertensive patients participated in the research. Creatinine serum and clearance were assessed to analyze kidney function. The GFR was estimated using the following formulae: Cockcroft and Gault (CG); CG-corrected; Modification of Diet in Renal Disease(MDRD)-6; MDRD-4 and The Chronic Kidney Disease Epidemiology Collaboration Equation(CKD-EPI). The following tests were used: weighted Kappa coefficient; Pearson’s correlation (r) and Bland-Altman graph analysis. The greatest agreement found using the weighted Kappa was for the CKD-EPI formula (k = 0.362). The greatest correlation was found for the CKD-EPI formula (r = 0.612). The CKD-EPI formula exhibited the lowest number of individuals below the lowest limit of agreement in the Bland-Altman analysis. The CKD-EPI formula should be used to estimate the GFR, given that it exhibited the greatest correlation and agreement with creatinine clearance; thus, it is possible to implement low-cost activities focusing on early detection and diagnosis, as well as the prevention of CKD.