Vanillic acid has multiferous applications in a variety of industrial sectors such as cosmetics, flavors, food, tobacco, pharma, beverages, alcohols, and polymer which makes it suitable for extraction from an aqueous system. Separation of vanillic acid from fermentation broths and aqueous streams (dilute) is however a challenging job. On that account, in the current analysis, the reactive extraction of vanillic acid from its aqueous solution has been investigated by using tri-n-butyl phosphate (TBP) in decanol, kerosene, and soybean oil as diluents at a constant room temperature of 298.15 +/- 1 K and an atmospheric pressure of 101.325 +/- 1 kPa. The terms such as degree of extraction (eta %), overall distribution coefficient (K-D), equilibrium complexation constant (K-E), and loading ratio (z) were used to calculate reactive extraction data. The equilibrium of reactive extraction of the vanillic acid-TBP system was explained with the help of the mass action law model. The effect of concentrations of the extractant, the initial acid, as well as the diluent type was investigated by experiments performed. Further detailed discussion on the solvent to be used and toxicity issues has been provided. This work can be regarded as the first attempt to study the reactive extraction process using TBP as an extractant in decanol, kerosene, and soybean oil for the separation of vanillic acid from the aqueous medium.