Electrical conductivity (σ) of aluminum chloride (AlCl₃) and 1-butyl-3-methylimidazolium chloride (BMIC) ionic liquid (IL) was investigated as a function of temperature and AlCl₃ mole fraction ( $X_{\mathrm{AlC}{\mathrm{l}}_3}$). Electrochemical impedance spectroscopy was used to measure the electrical conductivity. Composition of AlCl₃:BMIC ionic liquid was varied by changing the $X_{\mathrm{AlC}{\mathrm{l}}_3}$ from 0 to 0.67. The temperature was changed from 70°C to 110°C at 10°C intervals. It was found that the electrical conductivity increases with an increase in temperature. Electrical conductivity increases with $X_{\mathrm{AlC}{\mathrm{l}}_3}$ from 0 to 0.5 and then starts to decrease after $X_{\mathrm{AlC}{\mathrm{l}}_3}$ = 0.5. A species concentration profile was developed based on thermodynamic model at room temperature for the IL containing ${\mathrm{BMI}}^{+}$, ${\mathrm{Cl}}^{-}$, $\mathrm{AlC}{\mathrm{l}}_4^{-}$, $\mathrm{A}{\mathrm{l}}_2\mathrm{C}{\mathrm{l}}_7^{-}$, $\mathrm{A}{\mathrm{l}}_3\mathrm{C}{\mathrm{l}}_{10}^{-}$, $\mathrm{A}{\mathrm{l}}_4\mathrm{C}{\mathrm{l}}_{13}^{-}$, and $\mathrm{A}{\mathrm{l}}_2\mathrm{C}{\mathrm{l}}_6$ at different $X_{\mathrm{AlC}{\mathrm{l}}_3}$. The only anion species presents between 0 and 0.5 $X_{\mathrm{AlC}{\mathrm{l}}_3}$ are ${\mathrm{Cl}}^{-}$ and $\mathrm{AlC}{\mathrm{l}}_4^{-}$. Anions like $\mathrm{A}{\mathrm{l}}_2\mathrm{C}{\mathrm{l}}_7^{-}$, $\mathrm{A}{\mathrm{l}}_3\mathrm{C}{\mathrm{l}}_{10}^{-}$, $\mathrm{A}{\mathrm{l}}_4\mathrm{C}{\mathrm{l}}_{13}^{-}$, and $\mathrm{A}{\mathrm{l}}_2\mathrm{C}{\mathrm{l}}_6$ are found at higher $X_{\mathrm{AlC}{\mathrm{l}}_3}$. A good agreement between the model and the experimental data was obtained. The variations in anion concentration, molecular structure, and cation–anion interactions are to be the causes of the changes in electrical conductivity of AlCl₃:BMIC system.