New developing regulations of chemical-use on fruit calls for an integrated disease management approach using softer chemicals to reduce decay of fresh produce. The aim of this study was to evaluate the potential of essential oil volatiles to manage postharvest citrus decay. Fifteen essential oils were tested in vitro for its fungicidal properties against growth- and spore-germination of two postharvest citrus pathogens. Cinnamon bark and oregano oils were fungicidal to fresh mycelial-growth of Penicillium digitatum (cinnamon: ≥212.16; oregano: ≥106.08 µl/L headspace) and Galactomyces citri-aurantii (cinnamon: ≥106.08; oregano: ≥212.16 µl/L headspace). Oregano inhibited sporulation of P. digitatum (≥53.04 µl/L headspace). When spores of these pathogens were exposed to cinnamon essential oil (≥106.08 µl/L headspace) for 72 h, spore germination was inhibited by 99.8% (P. digitatum) and 99.3% (G. citri-aurantii). Combining cinnamon with oregano (both at 53.04 µl/L headspace) inhibited spore germination, whilst inhibiting sporulation of P. digitatum. Cinnamon (167.67 µl/L headspace) and oregano (83.84 µl/L headspace) tested in the absence of growth media were fungitoxic to 100% of P. digitatum spores. In vivo studies showed that cinnamon (133.00 µl/L headspace) reduces green mould (43.33±15.06% control) when tested on sterile-wounded ‘Valencia’ oranges in the presence of a fruit sporulating with P. digitatum, and that oregano (106.20 µl/L headspace) inhibits the sporulation on fruit injected with P. digitatum. These essential oils did not negatively affect degreening of ‘Eureka’ lemons when treated together with ethylene. This study demonstrates the potential use of cinnamon bark and oregano to manage postharvest decay of citrus during degreening.