We estimate the size of time-reversal violation in β decay due to the Kobayashi-Maskawa phase δ, and the θ term [Formula presented] We find that the contribution of δ to the [Formula presented] and [Formula presented] correlations is not likely to be larger than of the order of [Formula presented] and [Formula presented] respectively, where [Formula presented] for neutron and [Formula presented] decay. For the contribution of [Formula presented] to [Formula presented] and [Formula presented] we conclude that it is not likely to be larger than of the order of [Formula presented] and [Formula presented] respectively (the present experimental limits on [Formula presented] and θ are [Formula presented] and [Formula presented]), where [Formula presented] is the energy release in the decay. For both δ and [Formula presented] the [Formula presented] and [Formula presented] coefficients are dominated by long-distance contributions. The small values of [Formula presented] and [Formula presented] in the standard model compared to the best experimental limit on [Formula presented]-odd correlations ([Formula presented] for [Formula presented] in [Formula presented] decay) give potentially a wide window in which [Formula presented]-violating interactions beyond the standard model can be searched for. However, the range in this window that one will be able to exploit depends on the level at which the contributions of the final-state interactions can be kept under control.