Estrus synchronization and timed artificial insemination can be used to carry AI to small farmers. Present study compared two estrus synchronization protocols during low breeding season and recorded estrus incidence and conception rate after timed insemination in buffaloes that were exposed to a bull (BE, biostimulated) round the clock or not exposed to a bull (BN, not biostimulated). Fifty non pregnant, healthy Nili Ravi buffaloes received controlled intravaginal drug release (CIDR) cattle inserts (containing 1.38 gm progesterone) for 7 days for estrus synchronization. Animals also received GnRH or No GnRH injection on day of CIDR insertion.  Inseminations were made with frozen thawed buffalo semen at 58 hour after CIDR removal. Heat incidence did not differ among the treatment groups (P>0.05). Conception rate was higher in GnRH + BE group (87.5%) than that in GnRH + BN (37.5%) and No GnRH + BN ( 0.0%) groups (P<0.05). Conception rate did not differ between GnRH + BE (87.5%) and No GnRH + BE (60.0%) groups (P>0.05). It was concluded that bull exposure may be used to attain an improved conception rate in buffaloes synchronized for heat with CIDR during low breeding season.