The increasing rates of obesity and related health problems are largely attributed to the excessive consumption of high-fat foods. Thus, a fat substitute is proposed to replace the same functions of fats in food products. This study explored the potential of inulin as a fat substitute to produce low-fat muffins. Five batches of muffins, each with varying levels of inulin replacing oil (ranging from 0 to 100%), were prepared to examine how this substitution would impact the physicochemical and sensory properties of the muffins. Calorie content was determined using a bomb calorimeter, whilst the moisture, fat and fibre content were determined based on the AOAC International standard method. The muffin’s texture was analysed using a texture analyser, and the height was measured by calculating the average of different parts of the muffin. The acceptance level of muffins was conducted using a 9-point Hedonic scale. The addition of 15% inulin reduced the fat content by 68.05% and calories by 12.63% compared to the control without significantly affecting the physicochemical properties and sensory acceptability. Additionally, inulin provided the advantage of increasing fibre content by 82.76% when compared to the control sample. Increasing the amount of inulin also increased height and improved the aerated structure of muffins. The study provides evidence for the effectiveness of inulin as a fat replacer, which can help produce low-fat food products with good functional properties and nutritive value for health.