Fusion reactivity for the pB11 fuel has been reassessed for magnetic confinement devices. This study is based on two factors: new measurements of the fusion reaction cross-sections and an accounting of the kinetic effects that lead to the increase of the number of protons at higher energies (with respect to a pure Maxwellian). The net effect leads to an approximately 30% increase of the fusion yield for the same global plasma parameters compared to the previous assessments.