The accidental eccentricity provisions of IS 1893 are compared with other national codes and examined using Incremental Dynamic Analysis procedure in order to estimate collapse probabilities of mid-rise (4-, 8- and 12-storied) RC frame buildings. The buildings are designed for regular symmetric configuration following Indian codes and are considered with varying accidental eccentricities of 0% (regular symmetric), 5%, 10%, and 15%. The accidental eccentricity is introduced by changing the mass distribution on floor plan, keeping the total mass at each floor same as for a corresponding regular symmetric building. The obtained results (dynamic characteristics, torsional irregularity indices, dynamic capacity curves, collapse margin ratio and collapse probabilities) for regular symmetric buildings and buildings with accidental eccentricity are compared. It is observed that buildings with accidental eccentricity, on average, exhibit 1.8 and 1.4 times higher probability of collapse as compared to the corresponding regular symmetric buildings, for DBE and MCE demands, respectively.