Tag retention and tag-induced mortality were evaluated for 2 sizes of Hallprint® dart tags injected in largemouth bass (Micropterus salmoides). Mean tag retention rates of 98% for larger (81 mm) PDB dart tags and 78% for smaller (69 mm) PDT dart tags were observed during a 15-month study in Lake Blanchester, Florida. Significantly higher tag loss (P ≤ 0.05) of PDT tags was attributed to a more flexible and shorter (12-mm) barb (anchor) compared to the larger and longer (18-mm) barb on the PDB tag. Estimated tag-induced mortality was 13% for bass 260-299 mm using smaller tags, and 18% for bass ≥300 mm TL using larger tags, over a 3-month period in a hatchery pond. However, there were no significant differences (P > 0.05) in mortality rates between control and tagged fish for 3 size groups. The larger tags with 98% tag retention and no significant tag-induced mortality are recommended for long-term tagging studies in bass ≥300 mm.