Endometriosis-related pain has been predominantly medically managed, which has hindered understanding of psychological factors involved in these pain experiences. Models of chronic pain highlight the biased interpretation of ambiguous information as health threat related (interpretation bias) as an important process in the development and maintenance of chronic pain. Whether interpretation bias may also be similarly implicated in endometriosis-related pain is unclear. The current study aimed to address this gap in the literature by (1) comparing interpretation biases between a sample of participants with endometriosis and a control sample of participants without medical conditions and pain, (2) exploring relationships between interpretation bias and endometriosis-related pain outcomes, and (3) exploring whether interpretation bias moderated the relationship between endometriosis-related pain severity and pain interference. The endometriosis and healthy control samples comprised 873 and 197 participants, respectively. Participants completed online surveys assessing demographics, interpretation bias, and pain-related outcomes. Analyses revealed that interpretation bias was significantly stronger among individuals with endometriosis relative to controls, with a large effect size. Within the endometriosis sample, interpretation bias was significantly associated with increases in pain-related interference, however, interpretation bias was not associated with any other pain outcomes and did not moderate the relationship between pain severity and pain interference. This study is the first to evidence biased interpretation styles among individuals with endometriosis and to show this bias is associated with pain interference. Whether interpretation bias varies over time and whether this bias can be modified through scalable and accessible interventions to alleviate pain-related interference are avenues for future research.