To compare pulse oximeter, cold test, and electric pulp test for assessment of pulp vitality in immature permanent teeth. Materials & methods: A total of 50 teeth were enrolled. This cross-sectional study included permanent maxillary incisors in based on the degree of root development (complete or incomplete). The results were analysed using SPSS software. Results: Cold test and EPT diagnosed all endodontically treated teeth as non-vital (true positive). Pulse oximeter had the highest diagnostic accuracy with 96% sensitivity and 100% specificity. The PPV and NPV for pulse oximeter was 100% and 97.5%, respectively. Conclusion: Pulse oximetry has a higher specificity and better accuracy than the cold test and the electric pulp test in assessing the pulp vitality in the diagnosis of vital teeth