Deeply anesthetized and comatose states are often accompanied by a distinctive pattern of electroencephalographic activity, called “burst suppression”. This pattern’s underlying mechanism and functional significance remain largely unknown. In this work we demonstrated that burst suppression can be detected in fMRI data, without the need for accompanying measures of neural activity. We then used this fMRI approach to perform whole-brain mapping of burst suppression in anesthetized human volunteers and non-human primates. We found that burst suppression involves the same set of brain areas across primate species, and is mostly absent in primary visual and somatosensory areas.