We report an event-related brain potential (ERP) experiment that tests whether autistic adults are able to maintain and switch between counterfactual and factual worlds. Participants (N = 48) read scenarios that set up a factual or counterfactual scenario, then either maintained the counterfactual world or switched back to the factual world. When the context maintained the world, participants showed appropriate detection of the inconsistent critical word. In contrast, when participants had to switch from a counterfactual to factual world, they initially experienced interference from the counterfactual context, then favoured the factual interpretation of events. None of these effects were modulated by group, despite group-level impairments in Theory of Mind and cognitive flexibility among the autistic adults. These results demonstrate that autistic adults can appropriately use complex contextual cues to maintain and/or update mental representations of counterfactual and factual events.