AbstractPrediction is a central goal and a yet‐unresolved challenge in the investigation of oceanic rogue waves. Here we define a horizon of predictability for oceanic rogue waves and derive, via extensive computational experiments, a statistically converged predictability time scale for these structures. We show that this time scale is a function of the sea state (i.e., severity of the ambient ocean waves), the height of the anticipated rogue wave, and the level of uncertainties in the ocean measurements. The presented predictability time scale establishes a quantitative metric on the combined temporal effects of the variety of mechanisms that together lead to the formation of a rogue wave and is crucial for the assessment of validity of rogue wave predictions, as well as for the critical evaluation of results from the widely used model equations.