Antifungal expenditures are substantial for many hospitals. Using caspofungin for the treatment of candidemia accounts for a sizable proportion of the costs. A cost minimization study that used a decision analytic model was done to compare in-hospital diagnosis and treatment costs using the Candida albicans peptide nucleic acid fluorescence in situ hybridization (PNA FISH) test versus the C. albicans screen test for differentiating C. albicans from non-albicans Candida species bloodstream infections. Assuming physician notification of yeast identity concurrent with blood culture positivity, potential savings resulting from use of the C. albicans PNA FISH test compared with the C. albicans screen test averaged $1837 per patient treated, although laboratory costs for doing the C. albicans PNA FISH test ($82.72) exceeded those for the C. albicans screen test ($2.83). Savings were realized through a decrease in antifungal drug costs, particularly caspofungin. Incorporating the C. albicans PNA FISH test as part of the initial identification algorithm for yeasts recovered from blood can result in substantial savings for hospitals.