Background: The intellectual disability field has learned about the lives of people with intellectual disabilities (ID), largely from the perspective of their family and caregivers. Information from caregivers has been critical to scientific advancement, especially when caregivers are engaged on behalf of individuals with significant language impairment. On the other hand, the perspective of individuals with ID themselves is critical for internal subjective content such as thoughts and feelings. Methods: Participants were 90 adults with ID and a proxy of their choosing. Results: Overall, self and caregiver report were significantly related for subjective health but varied for physical activity, social support and stress. Conclusions: These findings add to the growing literature establishing the importance of considering the self-report of adults with ID, particularity when the subject matter focuses on internal thoughts or feelings. Clinical considerations for the use of self and proxy report are discussed.