Introduction: Biomimetic dentistry primarily focuses on achieving aesthetics that closely resemble natural enamel and dentin. This approach ensures that dental restorations seamlessly match the appearance of enamel and dentin, rendering them virtually invisible. Additionally, biomimetic dentistry aims to mimic not only the visual characteristics but also the physical properties of enamel and dentin, thereby ensuring functional acceptability. The introduction of new composite materials in the market is a gradual progression aimed at attaining the mentioned objectives. Aim: To compare clinical performance and colour matching of single and multiple shade composites in simple Class-I carious lesions after one year. Materials and Methods: This randomised clinical study included 21 patients with a total of 72 Class-I carious lesions with patients who provided informed consent. Teeth were randomised into two groups: Group-A (n=36) received multishade composite (3M Filtek z350), and Group-B (n=36) received single-shade composite (Omnichroma). Clinical performance was assessed by two blinded evaluators at baseline, six months, and one year using modified United States Public Health Service (USPHS) criteria. Colour matching was evaluated by capturing digital photographs with a DSLR camera, ring flash, and 100 mm macro lens. Colour measurements (L*, a*, b*) were analysed using Adobe Photoshop, and ΔE was calculated immediately after restoration. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS) 21.0 software, employing Chi-square test, Friedman test, and independent t-test. Results: No significant difference was found in clinical outcomes after one year using modified USPHS criteria (p>0.05). However, both Group-A (p=0.002) and Group-B (p=0.007) showed increased marginal discolouration, and decreased colour match (p<0.001) from baseline to one year. There was no statistically significant difference in colour matching potential between the two groups (p=0.056). Conclusion: Single-shade composites effectively treat Class-I carious lesions, demonstrating satisfactory colour matching and clinical performance. [ABSTRACT FROM AUTHOR]