Failure to file return on time triggers penalty under Section 271F even if return is later filed after reassessment notice.
The summary addresses penalty liability for failing to file the original income tax return by the statutory due date, noting that later filing in response to a reassessment notice does not excuse the late original filing. It emphasizes that initiation of penalty proceedings after completion of reassessment does not automatically vitiate the penalty, and that absence of a valid reason for delay sustains penal consequences under the provision for non-filing.