The purpose of this study was to determine critical components of the life history including otolith age validation, growth estimation, and reproductive characteristics for southern kingfish Menticirrhus americanus. A total of 2233 southern kingfish were collected from March 2009 to December 2010. Ages were estimated and validated using thin-sectioned otoliths. Marginal increment analysis showed a single annulus was deposited once a year between April and May. Growth was significantly different (P < 0.0001) between sexes Linf = 418.97 ± 16.58 mm, k = 0.29 ± 0.03, t0 = −1.30 ± 0.10 for females and Linf = 290.74 ± 6.93 mm, k = 0.52 ± 0.05, t0 = −1.08 ± 0.11 for males. Southern kingfish spawn from March to August with a peak spawn in April. Based on evidence of multiple oocyte maturation stages and post-ovulatory follicles (POFs) southern kingfish are multiple spawners exhibiting indeterminate fecundity. Spawning frequency for females ranging from 222 to 351 mm TL (age 1–5) was estimated as one spawning event every 2.0–4.2 days with up to 6 million total ova produced per spawning season per female.