Kinetic modelling of Arabian atmospheric residue (AR) and vacuum residue (VR) undergoing thermal cracking at 400 degrees C to 420 degrees C in an autoclave is detailed in this study. A five-lump model based on the gas, coke, asphaltene, maltene and distillate fractions is developed. Three reaction schemes encompassing 6, 10 or 13 reaction pathways, with the corresponding fitted parameters, are compared. Additionally, coke induction is captured using a step function. Fitting AR experimental results revealed that the root mean squared deviations (RMSE) for the 6-reaction scheme almost equalled the 10- and the 13-reaction schemes and the fit showed the same accuracy. The 6-reaction scheme model was then fitted to slurry catalytic thermal cracking of AR mediated by drill cuttings. A comparison between the kinetic parameters confirmed the catalytic role of the drill cuttings, despite their nonporous morphology, and lower activation energy for distillate formation was observed. Lastly, the 6-reaction, AR-fitted model was employed to predict experimental data from non-catalytic and catalytic thermal cracking of VR. The model could predict the non-catalytic runs to a better extent. Failure to predict the catalytic cracking of VR is attributed to rapid deactivation of the drill cuttings arising from the difference in the nature and concentration of asphaltenes and the hydrogen donors in the VR relative to the AR feedstock.