BACKGROUND: MGMT promotor methylation status is part of glioma diagnostics, supporting clinical decision making. Internationally different methods and cut-off levels are used to determine whether a tumor is methylated or unmethylated. Treatment decisions get unreliable, when methylation status of the tumor can change due to the analysis and cut-off used. METHODS: We conducted an international survey, consisting of 27 questions, to clarify which methods are regularly used in different clinico-pathological settings and why a specific method is selected. We also asked about opinions regarding an international consensus on methods and cut-off levels. RESULTS: The survey was answered by 146 respondents - mainly neuropathologists - from 24 countries. The responses show that MGMT methylation status is determined for all gliomas in 37% of laboratories, while 8% do not perform the analysis. The most commonly used methods are msPCR (37%) and pyrosequencing (34%). The main reasons for choosing a specific method are simplicity (56%), cost-effectiveness (49%) and reproducibility of results (49%). For those using pyrosequencing, the most common number of CpG sites analyzed is four, but varies between 1–3 and more than 16. For 50% of laboratories, the company producing the kit determines which CpG sites should be examined, while 33% select the sites themselves. Selection of cut-off is equally distributed between a cut-off a) published in the literature, b) defined by the lab or c) defined by the company performing the analysis. This cut-off varies between different pathology departments. In one lab tumor is determined as methylated in case of 1 methylated CpG site of 17 analyzed. For others cut-off for methylated varies from 1% to 30%. Some report tumor as unmethylated or weakly versus highly methylated. An international consensus on MGMT methylation method is believed to be of advantage by 66%, while only 20% do not find this necessary. A consensus on a cut-off is warranted by 76%. Most suggest that the consensus method should be msPCR (45%) or pyrosequencing (42%), while 17% suggest next generation sequencing. CONCLUSION: While analysis and use of MGMT methylation status has become routine in the clinico-pathological setting, there is still controversy regarding the best laboratory method and the clinically relevant cut-off level. Most respondents suggest that an international consensus on both method and cut-off should be established.