Determining age-and-growth for sharks impacted by commercial fishing is important for estimating key life-history characteristics for fisheries management. Carcharhinus coatesi and Rhizoprionodon acutus are bycatch in the Northern Territory (NT) Demersal Fishery. Vertebrae from 290 C. coatesi and 158 R. acutus were sampled between 2018 and 2019 from commercial trawl vessels. Ages were estimated by counting band-pairs on vertebrae and used to estimate age-at-maturity and growth parameters with a multi-model approach. Analysis were run for: (1) the entire sample, (2) with vertebrae deemed to have appropriate readability, and (3) with age estimates adjusted for time-of-birth for aseasonally reproducing sharks. Annual deposition of band formation could not be validated for either species. The VBGF model had the most support for both species and both sexes, and suggests sharks grow rapidly to asymptotic length. Age-at-maturity estimates were: C. coatesi females, A50 = 2.70 years (SE = 0.31), and males, A50 = 3.07 yrs (SE = 0.25); R. acutus females, A50 = 1.11 yrs (SE = 0.46), and males, A50 = 2.19 yrs (SE = 0.43). This provides important information for fisheries managers, however, there is need for further research on increment formation in vertebrae to confirm the validity of our age estimates.