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Information on biodegradation kinetics of biodiesel fuels is a key aspect in current risk and impact assessment practice and in selection of appropriate remediation strategies. Unfortunately, this information is scattered, while factors influencing variability in biodegradation rates are still not fully understood. Therefore, we systematically reviewed 32 scientific literature sources providing 142 biodegradation and 56 mineralization half-lives of diesel and biodiesel fuels in various experimental systems. The analysis focused on the variability in half-lives across fuels and experimental conditions, reporting sets of averaged half-life values and their statistical uncertainty. Across all data points, biodegradation half-lives ranged from 9 to 62 days, and were 2–5.5 times shorter than mineralization half-lives. Across all fuels, biodegradation and mineralization half-lives were 2.5–8.5 times longer in terrestrial systems when compared to aquatic systems. The half-lives were generally shorter for blends with increasing biodiesel content, although averaging data from various experiments masked differences in half-lives between different fuels. This in most cases resulting in lack of statistically significant effects of the type of blends and experimental system. Our biodegradation kinetic data can be used for improved characterization of risks and impacts of biodiesel fuels in aerobic aquatic and terrestrial environments. Future experiments are required to quantify biodegradation kinetics in anaerobic conditions. Generally higher biodegradability of biodiesel fuels may suggest that passive approaches to degrade and dissipate biodiesel contaminants in situ, like monitored natural attenuation, may be appropriate remediation strategies for biodiesel blends.