Objective: Immunocompromised patients with chronic inflammatory disease (CID) may have experienced additional psychosocial burden during the COVID-19 pandemic due to their immunocompromised status. This study was undertaken to determine if vaccination would result in improved patient-reported outcomes longitudinally among individuals with CID undergoing SARS–CoV-2 vaccination regardless of baseline anxiety. Methods: Data are from a cohort of individuals with CID from 2 sites who underwent SARS–CoV-2 vaccination. Participants completed 3 study visits before and after 2 messenger RNA vaccine doses in the initial vaccination series when clinical data were collected. Patient-reported outcomes were measured using the Patient-Reported Outcomes Measurement Information System 29-item Health Profile and expressed as T scores, with 2 groups stratified by high and low baseline anxiety. Mixed-effects models were used to examine longitudinal changes, adjusting for age, sex, and study site. Results: A total of 72% of the cohort was female with a mean ± SD age of 48.1 ± 15.5 years. Overall, sleep disturbance improved following both doses of SARS–CoV-2 vaccinations, and anxiety decreased after the second dose. Physical function scores worsened but did not meet the minimally important difference threshold. When stratifying by baseline anxiety, improvement in anxiety, fatigue, and social participation were greater in the high anxiety group. Physical function worsened slightly in both groups, and sleep disturbance improved significantly in the high anxiety group. Conclusion: Sleep disturbance decreased in a significant and meaningful way in patients with CID upon vaccination. In patients with higher baseline anxiety, social participation increased, and anxiety, fatigue, and sleep disturbance decreased. Overall, results suggest that SARS–CoV-2 vaccination may improve mental health and well-being, particularly among those with greater anxiety.