This paper discussed investigations on the Rapid Chloride Permeability Test (RCPT) and sorptivity test of concretes with replacement of cement by silica fume (SF), Ground Granulated Blast-Furnace Slag (GGBS), and glass powder (GP). The pozzolanic materials content was substituted at levels of 5%, 10%, 15%, and 20% by weight of cement. A series of concrete mixtures with varying proportions of SF, GGBS, and GP were prepared and subjected to both RCPT and water sorptivity test to measure their resistance to chloride ion penetration and rate of water absorption respectively. The specimens were cured under standard conditions and were subsequently tested at different ages. It was observed that all the concrete mixes incorporating different pozzolanic materials exhibited a similar trend in chloride penetrability and sorptivity. This observation can be attributed to the pozzolanic reaction products (CSH) effectively filling the pores between the cement pastes, which creates a denser concrete matrix and enhances durability. Consequently, it is suggested that pozzolanic concrete with up to 15–20% replacement could be suitable for various applications.