Catalytic combustion is a practical approach to sustain and manage combustion in microreactors. Previous work has demonstrated room-temperature ignition and size-dependent properties of platinum nanoparticles as they related to catalytic combustion of hydrocarbons. This work investigates the use of platinum nanoparticle coatings to combust a stochiometric methanol–air mixture. Platinum nanoparticles with dp = 8 nm were used to coat cordierite substrates with 800 μm wide square channels. Room-temperature ignition of the methanol–air mixture and repeated catalytic cycling were successfully achieved with operational temperatures ranging from 250 to 850 °C. The catalysis reaction was controlled by altering fuel–air flow rates and catalyst mass loading. A nanoparticle stability study indicated a minimal effect of sintering on the combustion behavior and vice versa with repeated catalytic cycling. A product gas analysis indicated that overall methanol conversion rates of up to 60% were achieved with the current design. The results of this work directly contribute to the development of catalytic micrometer-scale combustors.