OBJECTIVES: To estimate annual health care utilization and costs of pneumonia across age cohorts in the United State (US) from an all-payer perspective. METHODS: A retrospective cross-sectional study was conducted using the 2008 Medical Expenditure Panel Survey (MEPS) database, a nationally representative annual survey of the civilian non-institutionalized population of the US.  Pneumonia patients were identified as those with a Clinical Classification Code for pneumonia (code with 122).  Resources used and expenditures incurred by patients with pneumonia that were directly attributable to pneumonia treatment (physician office visits, emergency room visits, outpatients visits, inpatient visits, other medical visits, and medications) were estimated.  Health care costs per year per person (PYPP) were assessed across five age cohorts (<5, 5-<18, 18-<50, 50-<64, and ≥65 years old) and reported in 2008 US dollars. RESULTS:  A total of 297 patients (representing 3.1 million persons) reported using medical resources or incurring expenditures due to pneumonia.  Direct medical costs attributable to pneumonia were estimated at $2,763 (standard error [SE] ± 344) per patient.  Approximately 86% ($2,394) of this estimate was generated by inpatient hospitalizations for pneumonia, which were experienced by 26.9% of pneumonia patients, with an average of 0.31 admissions per patient.  Physician office visits and home health visits were the next largest categories of expenditure, contributing $153 (5.5%) and $113 (4.1%), respectively.  By age cohort, mean attributable costs PYPP for patients <5 (n=47), 5-<18 (n=38), 18-<50 (n=41), 50-<64 (n=108), and ≥65 years old (n=63) were $2,166 (±1043), $579 (±119), $1,747 (±$888), $2,983 (±556), and $4,201 (±553), respectively (p<0.05). CONCLUSIONS: This study provides an overview of clinical and economic burden of pneumonia in the US. Pneumonia-attributable expenditures were considerable, strongly driven by high inpatient hospitalization cost. In addition, patients aged ≥ 65 years had highest expenditures of pneumonia among all age cohort.