Inhibiting pancreatic lipase activity is an effective means of reducing fat absorption, which may have a role in combating obesity by limiting energy intake. The use of pharmaceutical lipase inhibitors has been limited due to the prevalence of undesirable side effects. Polyphenols represent an alternative strategy to inhibit digestive enzymes using safe, gentle, and cost-effective extracts derived from plant sources. Thus, this study evaluated alternative options by testing various polyphenol-rich plant extracts (grape seed, green tea, TeaVigo®, and white tea) for their ability to inhibit pancreatic lipase activity. Using an in vitro fluorescence assay, the relative potency of extracts tested was determined in comparison to the pharmaceutical orlistat. In addition, the most abundant catechins found in these extracts, epicatechin gallate (ECG), epigallocatechin (EGC), and epigallocatechin gallate (EGCG), were also tested for the ability to inhibit pancreatic lipase. Results showed the most effective plant-based lipase inhibitors were the concentrated green tea product, TeaVigo® and green tea. Results with the individual catechin trials showed EGCG and EGC were the most potent lipase inhibitors in the plant extracts.