A combination of high-level quantum-chemical simulations and sophisticated transition state theory analyses is employed in a study of the temperature dependence of the N2H+OH+HNNOH recombination reaction. The implications for the branching between and in the reaction are also explored. The transition N2H+OH N2+H2O NH2+NO state partition function for the recombination reaction is evaluated with a N2H]OH direct implementation of variable reaction coordinate (VRC) transition state theory (TST). The orientation dependent interaction energies are directly determined at the CAS+1+2/cc-pvdz level. Corrections for basis set limitations are obtained via calculations along the cis and trans minimum energy paths employing an Daug-pvtz basis set. The calculated rate constant for the recombination is found N2H+OH+HNNOH to decrease signi-cantly with increasing temperature, in agreement with the predictions of our earlier theoretical study. Conventional transition state theory analyses, employing new coupled cluster estimates for the vibrational frequencies and energies at the saddlepoints along the reaction pathway, are coupled with the VRC-TST analyses for the NH2+NO channels to provide estimates for the branching in the reaction. N2H+OH NH2+NO Modest variations in the exothermicity of the reaction (1-2 kcal mol-1), and in a few of the saddlepoint energies (2-4 kcal mol-1), yield TST based predictions for the branching fraction that are in satisfactory agreement with related experimental results. The unmodi-ed results are in reasonable agreement for higher temperatures, but predict too low a branching ratio near room temperature, as well as too steep an initial rise.