Abstract: In one embodiment, the invention is to a sample metering device, comprising a sample holding chamber oriented between a sample entry port and a sample isolation unit and having a diluent introduction port disposed therebetween for introduction of a diluent into the sample holding chamber. The volume within the sample holding chamber between the diluent introduction port and the sample isolation unit defines a metered volume of a sample for analysis. In another embodiment, the invention is to an apparatus and method for rapid determination of analytes in liquid samples by various assays including immunoassays incorporating a sample dilution feature, preferably suitable for low range sample dilution, and preferably capable of being used in the point-of-care diagnostic field.