Gas phase reactions of transition metal oxide cations (MO +) with alkanes are known to generate useful substances (e.g., alcohols). However, the products formed vary drastically depending on the metal and/or the alkane involved in the reaction. Previous calculations on these reactions have almost exclusively focused on methane, with almost all analyses based on DFT calculations. The reactions of chromium oxide cation (CrO +) involve crossings between spin surfaces, so the use of single reference methods to understand reaction mechanisms should be analyzed carefully. We have characterized the potential energy surfaces of the reactions of CrO + with methane, ethane, and propane using DFT, coupled-cluster, and multireference methods. We compare our results for methane calculations to previously reported studies and report original results for the reactions of ethane and propane. We use our high-level potential energy surfaces to better understand the reaction mechanisms involved in the transformations of alkanes by CrO +.