Whereas phototherapy is a safe and cost-effective treatment modality for psoriasis, economic disincentives discourage its use, including both direct and indirect costs to the patient. To determine when it may be cost-effective for patients to purchase a home light unit versus driving to clinic for outpatient phototherapy sessions. Estimates of expenses associated with 3 months of outpatient phototherapy were determined and compared to the price of a home phototherapy unit. Factors examined included the cost of gasoline (based on the national average), fuel efficiency of the vehicle, cost of owning and operating a motor vehicle, lost wages, and copayments. The cost for a standard 6-bulb narrowband UVB home unit is approximately $2600. Direct and indirect expenses imposed on patients increase with distance travelled to the dermatologist. If a patient lives 20 or more miles away from the dermatologist, the expenses associated with travel can total more than the out of pocket expense of purchasing a home phototherapy unit. This small analysis only accounted for the first 3 months of treatment and likely underestimates the total costs that patients would experience over a lifetime of treatment. It may be beneficial for physicians to educate patients on the cost-burden of in-office versus home phototherapy because patients can use these parameters to determine which option would be more cost-effective for them.