A theoretical study of the influence of mixing on reburning under laminar flow non-premixed conditions has been performed. Two models with a different level of detail of the fluid dynamics description have been developed and adapted. Models have been validated against experimental results. The models are able to reproduce the experimental trends of the influence of the studied variables: temperature, stoichiometry, velocity ratio between the streams, and reactant feeding configuration. Modeling and experimental results have been compared with plug-flow reactor (PFR) results, showing significant differences. Reactant injection mode involves a change in local stoichiometry and residence time distribution in the reactor, which seems to be the main influencing factor. For low temperatures, a higher NO reduction is obtained when local fuel-lean conditions have a longer residence time. For high temperatures, a higher NO reduction is obtained when local fuel-rich conditions have a longer residence time.