A thyroid nodule can be radiologically detected in up to 60% of the population. No single ultrasound feature is sensitive or specific for malignancy. Aims: To assess the ultrasound features in thyroid nodules of the Northeast Indian population in a tertiary care hospital. Objective: To correlate ultrasonography (USG) with the histopathological examination (HPE) findings after surgery using the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS). Materials and methods: This retrospective cohort study involved the records of 40 patients with thyroid nodules who had visited the Department of ENT in the year 2019–2020. Case records were retrieved and out of which only 28 patients had both USG findings and HPE reports. Results: Ultrasonography (USG) findings of 28 patients were analyzed and correlated with HPE reports. ACR TI-RADS had sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 70, 87, 82, and 77%, respectively, in diagnosing thyroid malignancy. The risk of malignancy (ROM) for ACR TI-RADS, 1, 2, 3, 4, and 5 groups in our study was 0, 0, 25, 71, and 100%, respectively. Conclusion: A specificity of 87% and PPV of 82% of ACR TI-RADS USG is good for diagnosing thyroid malignancy and planning further management in our population. We recommend the routine use of ACR TI-RADS USG classification systems. Clinical significance: Routine use of any widely accepted USG classification system should be employed. We recommend institutional studies of large sample sizes or audits to study the ROM for each target population to plan for population-specific treatment protocols.