The gas-phase reactions of CF+, CF2+, and CF3+ with perfluorobuta-1,3-diene (1,3-C4F6) have been studied using a selected ion flow tube (SIFT) instrument. Reaction rate constants and product branching fractions were measured at 300 K. The reactions all proceed with unit efficiency. The reactions of CF+ and CF2+ with C4F6 both proceed by two pathways : fluoride (F-) transfer and charge transfer. The ion CF3+ reacts with C4F6 by fluoride transfer exclusively. The results for CF3+ are compared with available data on reactions of CF3+ with C2F4 and higher perfluoroolefins.