Spring-calving cows were used to evaluate effects of calf age at weaning on production economics. Weaning treatments were early (calf age 150 d, EW), traditional (calf age 210 d, NW), and late (calf age 270 d, LW). Annual cow costs were greater for LW than EW and NW groups. Replacement heifer development costs were higher for EW compared to NW and LW heifers. Net income per finished steer was greater for EW and NW steers than for LW steers. When carcass data were adjusted to the fat depth of the EW steers, net income differences among groups were reduced. Breakeven for each system on a steer financial basis was lower for the NW and LW groups than for the EW group. Net income in each system is influenced by cow and replacement heifer costs and when finished steers, cull cows and heifers are marketed
