The use of ionic liquids (ILs) as alternatives to volatile organic liquids in solvent extraction is being considered in a number of applications. This study presents data on the dispersed phase holdup of the ionic liquid [bmim][PF6] with water in a Karr extraction column. It was found that this system conforms to the standard slip velocity relationships and that the holdup can be predicted using existing correlations for dispersed phase holdup in Karr reciprocating plate columns. This indicates that the incorporation of ionic liquids into existing processing equipment is relatively straightforward and they behave in a predictable manner.