Despite intense efforts, the mechanisms that drive glacial–interglacial changes in atmospheric pCO 2 are not fully understood. Here, we aim at quantifying the potential contribution of aeolian dust deposition changes to the atmospheric pCO 2 drawdown during the Last Glacial Maximum (LGM). To this end, we use the ocean circulation and carbon cycle model MPIOM/HAMOCC, including a new parameterisation of particle ballasting that accounts for the acceleration of sinking organic soft tissue in the ocean by higher density biogenic calcite and opal particles, as well as mineral dust. Sensitivity experiments with reconstructed LGM dust deposition rates indicate that the acceleration of detritus by mineral dust likely played a small role for atmospheric pCO 2 variations during glacial–interglacial cycles – on the order of 5 ppmv, compared to the reconstructed ∼80 ppmv-rise of atmospheric pCO 2 during the last deglaciation. The additional effect of the LGM dust deposition, namely the enhanced fertilisation by the iron that is associated with the glacial dust, played a more important role – leading to a pCO 2 -drawdown by more than 8 ppmv in our LGM sensitivity experiments despite an underestimated iron-limitation in the used model setup.