90,821 (95% CI, 81,912) over the same period. Lower extremity DVT accounted for 87.8% of diagnoses, and the risk of admission for iliofemoral DVT was 37.7% (36.6%-38.8%; P < .0001) higher than more distal DVT. Increased age was associated with risk of admission (risk difference, 4.7%-22%; P < .0001, for categories >18-34 years). Compared to patients with private insurance, the risk of admission was higher by 10.3% (95% CI, 9.4%-11.3%; P < .0001) for patients with Medicare and 10.0% (95% CI, 8.9%-11.0%) for patients with Medicaid. ED volume quartile (risk difference 10.8%; 95% CI, 7.6%-14.0%; P < .0001, for highest vs lowest volume quartile) and being treated at an investor-owned vs nonprofit (risk difference, 5.9%; 95% CI, 3.7%-9.0%; P < .0001) hospital were also associated with risk of admission. ED visits resulting in discharge had approximately twice the average charge of those that lead to admission ($2427 [95% CI, $2,344-$2,510] vs $1346 [95% CI, $1,290-$1,401]; P < .0001); however, the subsequent hospitalizations added an average of $25,195 (95% CI, $24,280-$26,112) per patient in additional charges.Conclusions: Despite the decrease in admission rates for isolated DVT, the overall numbers of admissions have increased. There are significant sociodemographic and structural factors associated with increased risk of admission for DVT. Strategies that address these factors may lead to improved care and reduced costs.