Background and Aims:Pre-operative investigations are performed before any surgical intervention under anaesthesia. Many are considered as routine. However, there are no clear guidelines regarding these in India. We aim to look at the relevance of the laboratory investigations ordered routinely and their cost implications compared with the National Institute of Clinical Excellence (NICE) guidelines.Methods:This prospective study was carried out at a tertiary care hospital. A total of 163 patients scheduled for elective surgical procedures were included in this study. Neither the surgeons nor anaesthesiologists involved in the case were aware of the study. The laboratory investigations of the patients who underwent surgery were noted. All values were categorised as normal or abnormal and they were assessed as indicated or unindicated based on NICE guidelines.Results:One hundred and sixty-three patients were subjected to a total of 984 tests. Forty three patients (26%) were subjected to tests as per NICE guidelines. Of the 984 tests, 515 tests were unindicated (52%). Out of the 515 unindicated tests, 7 (1.3%) were abnormal. None of these seven tests required any intervention or change of anaesthetic plan. The most common unindicated tests done were cardiac echocardiography and chest X-ray (92.5% and 93% respectively). The additional cost incurred towards unindicated tests was 63% of the total cost for the tests.Conclusion:Pre-operative laboratory investigations add to cost significantly. Patient premorbid conditions and surgical grade should guide the clinician to request for the relevant laboratory tests.