Keeping crude oil in pipelines flowing without interruption is of economic and strategic importance. Oils are complex mixtures and contain varying amounts of naturally occurring waxes. Because waxes can crystallize and stick to the wall inside the pipelines when the oil temperature falls below the wax appearance temperature, wax deposition is a significant challenge in flow assurance. It was noticed that certain waxes are stickier than others and are harder to treat. Because this behavior is not well understood, the effectiveness of the flow assurance programs is hindered and the billion dollar production assets are at risk. In this work, Nuclear Magnetic Resonance (NMR) Spectroscopy was employed to characterize the structures of the different types of waxes from various crude oils. Results demonstrated that the sticker waxes have branched carbon chains while the non-sticky waxes are mainly straight chain paraffins. This finding provides a molecular level basis for devising effective wax treatment programs.