The widely accepted belief that plain and lithium heparin containers are the choice for the collection of samples for renal function testing was investigated. This was conducted in addition to the effect of sampling conditions and diet types on renal function testing. A total of 100 subjects were recruited for the study, and renal function parameters such as creatinine, urea, uric acid, sodium, potassium, chloride, bicarbonate, and glucose were estimated using the Randox (UK) test kits on a semi-automated chemistry analyser (Contec-China). The containers used for the analysis include plain, lithium heparin, fluoride oxalate, and K2EDTA, whereas the sampling conditions were grouped into fasting, starvation, and random. The diet types consisted of carbohydrates, protein, and lipids. The results of the investigations were statistically analysed using One-Way Anova (Post-Hoc) on SPSS version 18-20 and level of significance pegged at 95%. The findings reaffirmed the suitability of plain and lithium heparin containers as the choice for renal function testing. Furthermore, sampling conditions were found not to have a palpable effect on the accuracy and precision of renal function parameters, whereas, lipid-rich diet impacted creatinine and urea concentrations. Conclusively, the gradation of the suitability index of routine containers for renal function test is plain > lithium heparin>K2EDTA>fluoride oxalate. Also, diet types should be considered when considering the clinical implication of renal function parameters.