We measured the vertical water column distribution of nitrous oxide (N2O) during the European Iron Fertilization Experiment (EIFEX) in the subpolar South Atlantic Ocean during February/March 2004 (R/V Polarstern cruise ANT XXI/3). Despite a huge build-up and sedimentation of a phytoplankton bloom, a comparison of the N2O concentrations within the fertilized patch with concentrations measured outside the fertilized patch revealed no N2O accumulation within 33 days. This is in contrast to a previous study in the Southern Ocean, where enhanced N2O accumulation occurred in the pycnocline. Thus, we conclude that Fe fertilization does not necessarily trigger additional N2O formation and we caution that a predicted radiative offset due to a Fe-induced additional release of oceanic N2O might be overestimated. Rapid sedimentation events during EIFEX might have hindered the build-up of N2O and suggest, that not only the production of phytoplankton biomass but also its pathway in the water column needs to be considered if N2O radiative offset is modeled. Copyright 2005 by the American Geophysical Union.