Bovine fasciolosis caused by Fasciola hepatica and Fasciola gigantica, is a neglected tropical snail-borne trematode disease of cattle that poses an adverse effect on animals' health culminating in economic damage. Cross-sectional investigation on coprological and postmortem assessment and economic significance of bovine fasciolosis in cattle slaughtered at Tarcha Municipal Abattoir, Southern Ethiopia through simple random sampling techniques was conducted from December 2020 to August 2021. Out of 384 cattle examined, 20.3% and 29.94% were found harboring Fasciola through coprological examination and postmortem examination respectively. The leading cause of fasciolosis in the study area was Fasciola gigantica (53.9%) as compared to F. hepatica (46.1%). The investigation revealed that the sex, origin, and body condition of the cattle has a statistically significant effect on the prevalence of bovine fasciolosis. The odds of male animals infested with fasciolosis were 2.25 times higher than female cattle and those of poor body-conditioned cattle were three times higher than cattle with good body condition. In postmortem examination, an average of 6 flukes were found in a single infested liver and the mean fluke count was (10 ± 1.97) in severely infested livers while in lightly infested livers (3± 1.79). Considering postmortem examination as the gold standard for diagnosis of fasciolosis, the sensitivity of the direct sedimentation technique was found to be 68% and the specificity 100% with substantial agreement (k = 0.74) between the two methods. The estimated yearly direct financial losses incurred owing to fasciolosis was around 2,227,536 2, Birr (47,945.24 USD). Thus, bovine fasciolosis is one of the economically important animal diseases in the study area, which necessitates integrated control measures to tackle its effect on animal health and subsequent economic impact.