A series of trialkyl carbamates of the general formula HC(Ph NHCOOCnH2n+1)3with n = 16, 18, 20 and 22 were synthesized from alkanols and tris(p-isocyanatophenyl)methane. The star-shaped compounds effectively depress the pour point of wax-containing paraffin oil. A quantity of 0.1 wt.% of the C18 derivative, by far the most effective depressant, reduces the pour point of paraffin oil containing 11.5 wt.% wax (mp 56–61° C) from 33° C to - 4°C. The extent of the depression varies with the concentration and composition of the wax. The depressants are ineffective when pure alkane waxes are added to the paraffin oil.