OBJECTIVES: To compare the effect of insurance coverage on health-care related expenditures among patients with arthritis in the United States. METHODS: A cross-sectional analysis was conducted. Subjects were derived from the National Medical Expenditures Panel Survey (MEPS) for those whom reported having any type of arthritis in 2009. A series of weighted univariate statistics were applied to examine patient’s demographic characteristics (gender, race, age, etc.) and insurance coverage (private, public, and uninsured). We further employed a generalized linear regression model to compare the health-care expenditures (inpatient, emergency room, outpatient, prescription drug) among different insurance status. All analyses utilized SAS PROC SURVEYs’ application to adjust for the complex sampling design employed by MEPS database.  RESULTS: There were an estimated 55.99 million arthritis patients from 2009 MEPS, in which 8.5 million (15.1%) had rheumatoid arthritis; 21.2 million (37.7%) had osteoarthritis; and 26.5 million (47.2%) had unspecified arthritis.  It is estimated that the majority of the arthritis patients 34.9 million (62.35%) were covered by private insurance, 16.5 million (29.5%) were covered by public plans and about 4.5 million (8%) were uninsured. The total medical expenditure for patients with arthritis in 2009 was $522.6 billion. Total prescription expenditures among arthritis patients were $122.1 billion. Per capita medical care expenditures among private, public and uninsured arthritis patients averaged $8,751, $12,093 and $3,730 respectively (P<0.0001). Also, there is a significant difference (P<0.0001) in the prescription expenditures among private, public and uninsured arthritis patients. Average prescription expenditure is $1982.6, $2991.6 and $748 respectively. CONCLUSIONS: Our findings indicate that uninsured arthritis patients had significant lower costs in total health-care expenditure than insured patients. Consistently with other studies, the uninsured have more unmet health needs than insured Americans. Such undertreated and/or underutilized situation may place uninsured people at risk of a serious disability complication.