A proper mechanistic understanding of the deaggregation process of small colloidal particle aggregates is of generic importance within many fields of science and engineering. The methodology for modeling colloidal deaggregation is currently limited to analytical solutions in the two-particle case and time consuming numerical algorithms, such as Brownian Dynamics (BD) simulations, for many-particle aggregates. To address this issue, a simplified alternative model that describes deaggregation of few-particle aggregates is presented. The model includes end-particle deaggregation and a particle reconfiguration mechanism, which are the two most important mechanisms for deaggregation. Comparison of the calculated first passage time distribution for various two-, three-, four-, and five-particle aggregates with the corresponding result using BD simulations confirms the validity of the model. It is concluded that the dominating mechanism behind deaggregation can be quantified using a deaggregation number, which reflects the time scale for reconfiguration relative to the time scale for end-particle deaggregation. (c) 2014 American Institute of Chemical Engineers AIChE J, 60: 1863-1869, 2014