Addition of fat and calcium sulfate to diets fed to ruminants has been shown to reduce methane production, but these factors have not shown effects on energy balance. A study using indirect calorimetry and 16 multiparous (8 Holstein and 8 Jersey) (78 ± 15 DIM; mean ± SD) lactating dairy cows was conducted to determine how mitigating methane by adding corn oil or calcium sulfate to diets containing reduced-fat distillers grains, affect energy and nitrogen balance in dairy cattle. A replicated 4 × 4 Latin square design with 35 d periods (28 d adaption and 7 d collections) was used to compare 4 different dietary treatments. Treatments were composed of a control (CON) diet which did not contain reduced-fat distillers grain plus solubles (RFDDGS), and treatment diets containing 20% (DM basis) RFDDGS (DG), 20% RFDDGS with 1.38% (DM basis) added corn oil (CO), and 20% RFDDGS with 0.93% (DM basis) added calcium sulfate (CaS). Addition of CaS reduced (P = 0.02) and addition of CO tended (P = 0.17) to reduce methane production compared with CON diet (421.6, 429.5, 394.7, and 381.4 ± 14.41 L/d for CON, DG, CO, and CaS respectively). Digestible energy was greater (P < 0.01) for DG and CO treatments compared with CON and CaS treatments (57.2, 61.5, 61.4, and 58.5 ± 1.13 for CON, DG, CO, and CaS, respectively). Metabolizable energy was greater (P < 0.01) in treatments containing RFDDGS compared with CON (50.5, 54.8, 55.0, and 52.3 ± 1.07 for CON, DG, CO, and CaS, respectively). Net energy of lactation per unit of DMI was greater in DG and CO than CON (1.44, 1.52, and 1.33 ± 0.04 Mcal/kg for DG, CO, and CON, respectively). Tissue energy was greater (P = 0.05) in DG and CO compared with CON (5.51, 6.48, and 2.71 ± 0.98 for DG, CO, and CON, respectively. Nitrogen balance was greater (P = 0.03) in DG than CO (91.1 vs 56.6 g/d for DG and CO, respectively). Added oil and calcium sulfate to diets containing RFDDGS may be a viable option to reduce methane emissions without affecting energy balance in lactating dairy cows.