Summary: This paper presents a hybrid model (stochastic/deterministic) that describes the time evolution of chemical species in a homogeneous gas-phase combustion reaction process at constant volume. First, currently employed stochastic algorithms are briefly introduced. Next, the development of the hybrid algorithm is detailed. The model is then validated and tested using a reduced reaction mechanism for methane combustion. The effect of user-input performance parameters on stochastic behavior and computational time is studied. The computational time of the algorithm compared to the stochastic simulation algorithm is then compared, and finally, the effect of multiple runs on auto-ignition time is investigated.