While reading is an essential human skill, the neuronal mechanisms supporting proficient reading are not well understood. In spite of the reduced visual acuity, parafoveal information plays a critical role in natural reading. However, it is debated whether words are previewed parafoveally at the lexical level. This is a key dispute for competing models on reading. We found neural evidence for lexical parafoveal previewing by combining a novel rapid invisible frequency tagging (RIFT) approach with magnetoencephalography (MEG) and eye-tracking. In a silent reading task, target words were tagged (flickered) subliminally at 60 Hz. The tagging responses measured when fixating on the pre-target word reflected parafoveal previewing of the target word. We observed stronger tagging responses during pre-target fixations when followed by low compared to high lexical frequency targets. Moreover, this lexical previewing predicted individual reading speed. Our findings demonstrate that reading unfolds in the fovea and parafovea simultaneously to support fluent reading.