As a byproduct of processing iron ore, a million tons of iron ore tailings (IOT) are deposited annually into quarries, landfills, rivers, and the ocean, creating environmental issues. The main objective is to evaluate the effectiveness of IOT as alternative for fine aggregate in concrete and to compare results with control concrete. Concrete mixes were designed with 0, 10, 20, 30, 40, and 50% IOT as substitutes for fine aggregate (river sand) while maintaining ratio of water-to-cement as 0.45. Concrete incorporated with IOT was evaluated for workability, compressive, split tensile and flexural strengths, water absorption, and acid attack. The sieve analysis results indicated that IOT conformed to the specifications of Zone II, as per IS: 383–2016. Concrete, including a varying IOT substitutions, exhibited decreased workability and consistently superior strength parameters relative to traditional concrete, especially up to a 30% replacement percentage. However, with an increased substitution of IOT compared to control concrete, the increased water absorption, weight loss, and strength loss in concrete mixes caused by acid attack, exhibited negligible adverse effects on durability parameters. The substitution of IOT with river sand in concrete is advised to avoid depletion of natural resources, reduce costs, and mitigate environmental issues.