Background: Pulmonary tuberculosis (TB) remains a major public health issue in India, with high incidence and mortality. The current literature on post-TB sequelae functional defects focuses heavily on spirometry, with conflicting obstruction vs. restriction data, lacks advanced statistical analysis, and has insufficient data on diffusion limitation and functional impairment. Objective: This study aimed to thoroughly evaluate post-tubercular sequelae after treatment, assessing chest radiology, spirometry, diffusing capacity, and exercise capacity. Methods: A total of 85 patients were studied at a university teaching hospital in Mysuru. The data collected included characteristics, comorbidities, smoking history, and respiratory symptoms. The investigations included spirometry, DLCO, chest X-rays with scoring, and 6MWT. Results: Of the patients, 70% had abnormal X-rays post-treatment, correlating with reduced lung function. Additionally, 70% had impaired spirometry with obstructive/restrictive patterns, and 62.2% had reduced DLCO, with females at higher risk. Smoking increased the risk of sequelae. Conclusions: Most patients had residual radiological/lung function abnormalities post-treatment. Advanced analyses provide insights into obstructive vs. restrictive defects. Ongoing research should explore pathogenetic mechanisms and therapeutic modalities to minimize long-term post-TB disability.