Technical Abstract: Modification of cottonseed quality traits is likely to be achieved through a combination of genetic modification, manipulation of nutrient allocation and selective breeding. Oil and protein stores comprise the majority of mass of cottonseed embryos. A more comprehensive understanding of the relationship between lint quality, lint yield and embryo reserve accumulation will help assist breeders in their efforts to improve seed value. Here we report the development of a rapid, non-destructive, simultaneous method for quantifying oil and protein levels within cottonseed by low-field 1H time-domain nuclear magnetic resonance (TD-NMR). This approach is suitable for a minimal amount of seed and represents an accurate (oil R2 = 0.998, protein R2 = 0.95), non-invasive alternative to conventional, time consuming chemical extractions. We demonstrate the value of this approach by surveying seed reserve content, identifying extremes of either protein and/or oil, in two sets of diverse germplasm.