OBJECTIVES: To evaluate healthcare costs among newly diagnosed patients with multiple myeloma (MM) in the US. METHODS: Patients newly diagnosed with MM who did not receive stem cell transplant were identified from the MarketScan Commercial and Medicare claims databases (1/1/2009-9/30/2015). All patients had continuous medical/prescription coverage 12 months before (baseline) and ≥12 months after the index date of MM treatment initiation. Demographics and clinical characteristics were evaluated during the baseline period. Healthcare costs (payments paid by insurance, patient, and other payers) and out-of-pocket (OOP) payments (copayments, co-insurance, and deductibles paid by patients) were determined among patients with age <65 and ≥65 years old and were inflation adjusted to 2015 US dollars. RESULTS: Among younger MM patients (<65 years; n=1,315), mean age was 56.7 years and 55.6% were male. During the follow-up, total mean healthcare costs (inpatient, outpatient, outpatient prescription) were $15,183 per-patient-per-month (PPPM). Inpatient costs were $4,204 PPPM, total outpatient medical costs were $8,100 PPPM. The total outpatient pharmacy costs were $2,880 PPPM including MM drug prescription costs of $2,521 PPPM. Among older MM patients (≥65 years; n=1,923), mean age was 76.6 years and 55.2% were male. During the follow-up, total mean healthcare costs were $8,277 PPPM. Inpatient costs were $1,583 PPPM, total outpatient medical costs were $4,448 PPPM, total outpatient pharmacy costs were $2,245 PPPM including MM drug prescription costs of $2,004 PPPM. Approximately 2% of total healthcare costs were OOP for both younger ($297 PPPM) and older MM patients ($181 PPPM), with approximately 16% of total OOP payments attributed to MM drug related outpatient services. CONCLUSIONS: Monthly total healthcare costs among both younger and older patients with MM are substantial with outpatient medical costs representing over half of the total healthcare costs.