Introduction: It is not clear whether older adults with chronic disease and their caregivers are likely to use patient portals. Methods: Older adults with a diagnosis of chronic obstructive pulmonary disease or congestive heart failure were evaluated as well as their caregivers. We explored whether these patients and/or their caregivers were able to use common portal elements. The perspective of informatics experts was ascertained using cognitive walkthrough methodology. Results: Fourteen patients and nineteen caregivers were evaluated. Patients required more time on all tasks than caregivers. Patient comments included a request for written instructions for using the system and a guide for interpreting lab results. Caregiver suggestions included improving color contrast and presentation of the current medication list. In the cognitive walkthrough, numerous problems were identified. Conclusions: Older adults with chronic illness and caregivers were interested in using a patient portal however multiple barriers were identified.