Ninety-nine young-of-the-year (YOY) California halibut (Paralichthys calif ornicus), collected from Bahia de Todos Santos (BTS, n = 29), Estero de Punta Banda (EPB, n = 36) and Bahia de San Quintin (BSQ, n = 34), Baja California (Mexico), were aged using sagittal otoliths. Our preliminary age de- termination by use of annual increments in otoliths of California halibut from Bahia de Todos Santos, and Estero de Punta Banda, Baja California (Mexico), showed that a minimum length of 180 mm SL could be set as limit size for halibut young-of-the-year. The separate age-length relationships between YOY halibut from these three study sites are described by linear equations: BTS: y = -4.943 + o.5x, r 2 = 0.899; EPB: y - -12.85 + 0.496x, r 2 = 0.903; BSQ: y = -28.19 + 0.5 19x, r2 = 0.967. The "y" is the standard length (mm) and the "x" is the age in days. Age was equivalent to the days from hatching. The Analysis of Covariance indicated no significant differences in growth rates between the three sites (ANCOVA, p = 0.419). Therefore, all data were combined to deter- mine one overall growth equation for young-of-the-year: y = —14.09 + 0.492x, (n = 99, r 2 = 0.907, S.E. constant = 6.25, S.E. slope = 0.059). This equation established a limit size for young-of-the-year halibut as 173 mm SL, with a range of readings between 168 to 180 mm.