Technical Abstract: Eleven surfactants were evaluated for their immobilizing and killing effects against the red imported fire ant. Reported here are the data on workers. Research on other castes is in progress. Although fire ants can be immobilized in most aqueous surfactant solutions within minutes, they can recover after been submerged in the solution for hours. There was a significant difference in time needed to immobilize and kill the ants among surfactants. Two of the 11 surfactants tested killed all the fire ants within 12 h of immersion. A negative correlation was found between hydrophilic-lipophilic balance (HLB) values of 9 of the non-ionic surfactants and mortality of the fire ant workers. The quick immobilizing effect of surfactants can potentially be used in formulations of mound drench products. Surfactants alone may also be useful in some specific scenarios of fire ant control, such as the dipping treatment in fire ant quarantine, which consequently could reduce the use of synthetic insecticides.