A process for the catalytic reduction of nitrous oxide using NHC‐ligated copper(I) tert‐butoxide precatalysts and B2pin2 as the reductant is reported. The reaction proceeds under mild conditions via copper(I)‐boryl intermediates which react with N2O by facile O‐atom insertion into the Cu–B bond and liberate N2. Turnover numbers > 800 can be achieved at 80 °C under 1 bar N2O.