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Formic acid binds to the SF$\mathrm{6-}$ anion in a single (OH-F) H bond, with the CH group weakly tethered to a neighboring F atom. Similar to the case of SF$\mathrm{6-}\cdot$ H$2$O complexes, the SF bond involved in the (OH-F) H bond is significantly stretched and weakened by the attachment of the HCOOH ligand. The complex undergoes a reaction upon infrared absorption of one quantum in the OH or CH stretching mode of the formic acid moiety, leading predominantly to the formation of SF$\mathrm{4-}$, HF, and CO$2$. The reaction can be inhibited by attachment of two Ar atoms. We present IR photodissociation spectroscopy results and theoretical data illustrating the reaction mechanism.