The present invention provides assay methods that increase the number of samples and/or target nucleic acids that can be analyzed in a single assay. In certain embodiments, an assay method entails separately subjecting S samples to an encoding reaction that produces a set of T tagged target nucleotide sequences, each tagged target nucleotide sequence including a sample-specific nucleotide tag and a target nucleotide sequence. In some embodiments, an assay method entails separately subjecting S samples to an encoding reaction that produces a set of T tagged target nucleotide sequences, each tagged target nucleotide sequence including a first nucleotide tag linked to a target nucleotide sequence, which is linked to a second nucleotide tag. In either case, the tagged target nucleotide sequences from the S samples can be mixed to form an assay mixture and subsequently assayed.