Four experiments were conducted to characterize the interactions between fumaric (FA), malic (MA), or citric acid (CA) and NaHCO3. In two experiments, seven diets were formulated containing 2.5% FA, MA, and CA, with or without 2.3, 1.9, or 1.4% NaHCO3, respectively, as well as a control diet (no addition of organic acids or NaHCO3) for 28-d-old pigs (Exp. 1, corn-soy protein concentrate-based diet) and 1-wk-old chicks (Exp. 4, corn-soy-based diet). In Exp. 1, at 2 and 4 wk, the FA+NaHCO3 treatment resulted in greater average daily gain (ADG) and feed intake (ADFI) compared with the control (P < .05). In Exp. 2, 28-d-old pigs were fed corn-soy diets with .9, 1.6, and 2.3% NaHCO3 in addition to 2.5% FA. After wk 2, there was a quadratic response in ADG (P < .08) and ADFI (P < .05) when increasing levels of NaHCO3 were added to the diet. This was true at wk 4 for both ADG and ADFI (P < .05). In Exp. 3, finishing pigs were fed corn-soy diets containing 2.5% FA or 2.5% FA + 2.3% NaHCO3 added to a control diet. No effect (P < .05) of FA or NaHCO3 was observed. In Exp. 4, the combination of CA+NaHCO3 or MA+NaHCO3 was superior to FA+NaHCO3 for ADG (P < .08) and ADFI (P < .05) when fed to young chicks.