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Invasive candidiasis, including bloodstream infection (candidemia), encompasses the most severe forms of <i>Candida</i> infection. Several species-specific and non-specific serological assays are commercially available to aid in diagnosis. This study compared the performance of five such biomarker assays. Serum samples from 14 patients with proven or probable invasive candidiasis, and from 10 control patients, were included in the analysis. A total of 50 serum samples were tested using <i>C. albicans</i> germ tube antibody (CAGTA) assay (Vircell), <i>C. albicans</i> IgM, <i>C. albicans</i> IgG and <i>Candida</i> mannan assays (Dynamiker Biotechnology). Among these samples, the β-1-3-D-glucan (BDG) assay (Fungitell), a laboratory standard for the diagnosis of invasive candidiasis, was positive in 20 (40%), intermediate in five (10%) and negative in 25 (50%). In cases of proven or probable candidemia, the sensitivity and specificity of the BDG assay was 86% and 80%, respectively; the <i>Candida</i> mannan assay, 14% and 86%; the CAGTA test, 57% and 60%; the <i>C. albicans</i> IgM assay, 71% and 60%; and <i>C. albicans</i> IgG assay 29% and 90%. In 4/8 (50%) cases with multiple serum samples, <i>C. albicans</i> IgM was positive sooner than BDG. Thus, when used as a rule-out test for invasive candidiasis, our data suggest that the <i>C. albicans</i> IgM assay may assist antifungal stewardship (over serum BDG).