This study numerically evaluates the effect of secondary flow on the reaction performance in heterogeneous gaseous spiral coiled reactor utilizing selective wall coatings. Laminar multispecies gas flow in spiral coiled reactor with circular and square cross-section is investigated using a validated three-dimensional computational fluid dynamics (CFD) model. Various selective wall coating strategies are evaluated within a range of Reynolds number. The reactor performance is measured not only based on the conversion rate but also in terms of figure of merit (FoM) defined as reaction throughput per unit pumping power and catalyst coating active area. The results indicate that secondary flow enhance reaction performance and improve catalyst utilization, especially at the outer wall. By maximizing this effect, the requirement of expensive catalyst materials can be minimized. This study highlight the potential of selective catalyst coating in coiled reactor for process intensification and cost reduction in various applications. © 2016.