Expectations about a food can impact on its taste, but this may represent a perceptual change or a bias in response at the decision-making stage. We hypothesised that expectation of taste intensity should be underpinned by modulation of activity in primary taste cortex. Using functional magnetic resonance imaging, we found that expecting a very sweet drink, but receiving a less sweet drink, enhanced the reported sweetness and bolstered activity in taste cortex, relative to a less sweet drink without this expectation. The activation overlapped with primary taste cortex activation found in 11 recent taste studies. Our findings provide evidence that taste expectation modulates activity in an area consistently reported as primary taste cortex, implying that expectation effects do indeed impact on taste perception.