Suppression of nitrous oxide (N₂O) emissions from soil is commonly observed after amendment with biochar. The mechanisms accounting for this suppression are not yet understood. One possible contributing mechanism is N₂O sorption to biochar. The sorption of N₂O and carbon dioxide (CO₂) to four biochars was measured in an anhydrous system with pure N₂O. The biochar data were compared to those for two activated carbons and other components potentially present in soils—uncharred pine wood and peat—and five inorganic metal oxides with variable surface areas. Langmuir maximum sorption capacities (Q_max) for N₂O on the pine wood biochars (generated between 250 and 500 °C) and activated carbons were 17–73 cm³ g^–1 at 20 °C (median 51 cm³ g^–1), with Langmuir affinities (b) of 2–5 atm^–1 (median 3.4 atm^–1). Both Q_maxand b of the charred materials were substantially higher than those for peat, uncharred wood, and metal oxides [Q_max 1–34 cm³ g^–1 (median 7 cm³ g^–1); b 0.4–1.7 atm^–1 (median 0.7 atm^–1)]. This indicates that biochar can bind N₂O more strongly than both mineral and organic soil materials. Q_max and b for CO₂ were comparable to those for N₂O. Modeled sorption coefficients obtained with an independent polyparameter—linear free-energy relationship matched measured data within a factor 2 for mineral surfaces but underestimated by a factor of 5–24 for biochar and carbonaceous surfaces. Isosteric enthalpies of sorption of N₂O were mostly between −20 and −30 kJ mol^–1, slightly more exothermic than enthalpies of condensation (−16.1 kJ mol^–1). Q_max of N₂O on biochar (50000–130000 μg g^–1 biochar at 20 °C) exceeded the N₂O emission suppressions observed in the literature (range 0.5–960 μg g^–1 biochar; median 16 μg g^–1) by several orders of magnitude. Thus, the hypothesis could not be falsified that sorption of N₂O to biochar is a mechanism of N₂O emission suppression.