The title compounds consist of a bornane skeleton with attached acetamide, C12H21NO (+/-)-(1) {systematic name: (+/-)-N-[(1RS,2RS,4RS)-1,7,7-trimethylbicyclo[ 2.2.1]heptan-2-yl]acetamide}, and chloroacetamide, C12H20ClNO (!)-(2) {systematic name: (!)-2-chloro-N-[(1RS,2RS,4RS)-1,7,7-trimethylbicyclo[2.2.1]- heptan-2-yl]acetamide}, functionalities to the 2-exo-position. The crystal structure of the first monoclinic polymorph of (+/-)-(1) has been reported previously [Ung et al. (2014). Monatsh. Chem. 145, 983–992]. Compound (+/-)-(1) crystallizes in the space group P21/n with two independent molecules in the asymmetric unit, in contrast to the above-mentioned polymorph which crystallized in the space group C2/c with one molecule in the asymmetric unit. In the title compounds, the bicyclic bornane moieties have normal geometries. In the crystals of both compounds, molecules are linked by N—H" " "O hydrogen bonds, reinforced by C—H" " "O contacts, forming trans-amide chains propagating along the a-axis direction. In the case of compound (!)-(1), neighbouring chains are linked by further C—H" " "O contacts, forming double-chain ribbons along [100].