The biological conversion of coal to methane can be an efficient and environmentally friendly means of utilizing the current coal reserves, including those that are difficult to utilize with conventional methods. Understanding the details of microbial coal degradation leading up to methanogenesis is essential in order to establish new energy production techniques and industrial processes that are cost- and energy-effective. Various approaches, such as bioaugmentation, biostimulation and physical, chemical and biological pretreatment for the purpose of enhancing methane yield are reviewed. Specifically for biostimulation which holds great promise for the success of biogasification, detailed reviews are provided on elucidating the composition of a microbial community, developing suitable nutrient solutions, and the in situ application of laboratory generated results. In addition, future research directions for maximizing methane production from coal are recommended. Published by Elsevier Ltd.