Continuous assessment of voltage stability is vivacious in safeguarding the electrical power system (EPS) operation. The final outcome of voltage instability is proximity to voltage collapse. The critical operating conditions of the transmission lines may possibly lead to voltage collapse with certain disturbances in electrical power supply. Quite a lot of Voltage Stability Indices (VSIs) have been technologically advanced in to estimate the proximity to voltage collapse. A few VSIs are computationally efficient, while the rest are said not to accomplish as expected under all circumstances. The study recommends a voltage stability index such as Composite Severity Index (CSI) and New Voltage Stability Index (NVSI) which are vigorous based on its theoretical nitty-gritties. The recommended index has been meritoriously tested on IEEE 30 bus and IEEE 118 bus test system under various operating conditions in order to weigh its efficacy. Also, it is shown that CSI and NVSI index could be used for estimating the distance to Voltage Collapse Point (VCP). The validation is done with Lmn, LQP and FVSI indices. The results designate its possibilities for the assessment of voltage stability. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group.