There is no reported data on the reproducibility of the IMMY lateral flow cryptococcal antigen test, which has a bearing on the need for parallel testing for following changes in titre over time. For 25 IMMY lateral flow cryptococcal antigen tests (7 cerebrospinal fluid, 18 serum) performed for clinical use in 9 patients we compared the original titre to the titre when retested from storage at 4°C. Titres as doubling dilutions were in the range of 3 to16 (i.e. compared to a baseline titre of 1:5, range of 1:40 to 1:327680). Median time between retesting the same sample was 48 days, range 3-730 days. Titres showed good correlation with retesting, correlation coefficient= 0.924 (95% CI 0.840-0.967). The mean difference for the retest was -0.28 dilutions, standard deviation 1.31, range -3 to +2 dilutions. Compared to the original titre, 76% of retests were within 1 dilution different, 92% within 2 dilutions different. This small study demonstrates the IMMY lateral flow cryptococcal antigen test has good reproducibility, and more than 2 dilutions change is likely to represent a true change in titre rather than variability of the test.