Stabilizing compositions for stabilizing a post-draw, but pre-analysis sample include, a saccharide, at least one heavy metal salt, and a pH from 5.9 to 8.0. The stabilizing compositions may include an aliphatic aldehyde, a buffer, and a preservative. The stabilizing compositions stabilize a sample for analysis. The analysis preformed on the stabilized cell may determine the state of a condition of interest, quantification of absolute cell counts, cellular activity, and qualitative analysis of cell types. Stabilizing a sample means that cells of the sample retain their biophysical properties, including biophysical properties of cell surface markers, for analysis. Preferably, the stabilizing compositions and methods may stabilize a sample for at least 16 days, and up to 30 days. The stabilizing compositions and methods may stabilize a sample for up to 180 days.
