The 17 Y-chromosomal short tandem repeats (STRs) included in the AmpFlSTR YFiler Amplification Kit (AB Applied Biosystems) (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 and GATA H4.1) were typed in 250 samples from Portugal. A total of 231 different haplotypes were found, where 17 haplotypes were shared by two individuals and one haplotype by three. The overall haplotype diversity (HD) was 0.9994. DYS458 non-consensus alleles found in 5 samples (out of 85) are all associated with paragroup J*(xJ1,2). Population comparisons with available Yfiler loci data in European samples were undertaken, namely with Northern Portuguese data (N=174) where no significant differences were observed with our sample (Rst=0.0000; P=0.8649+/-0.0310). Since both Portuguese databases can be joined (N=424; HD=0.9997; 394 distinct haplotypes), a study on the best loci for HD increment in this sample was also undertaken: by fixing the haplotypes generated from the minimal haplotype and SWGDAM core set (www.yhrd.org) and adding the other Yfiler loci one by one, the order in which the loci contribute more is DYS458, DYS456, GATA H4.1, DYS437 or DYS635, and finally DYS448. Therefore, at least in this population sample, all Yfiler loci are contributing for haplotype discrimination.