The electrochemical reduction of 0.1 M TaF5 in two hydrophobic ionic liquids (1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl) trifluorophosphate ([Py1,4]FAP) and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl) amide ([Py1,4]TFSA) is probed using three in situ techniques: scanning tunneling microscopy (STM), atomic force microscopy (AFM), and electrochemical quartz crystal microbalance (EQCM). These techniques reveal that under similar conditions TaF5 is more easily reduced in the liquids with [TFSA]- than [FAP]-anions. Increasing the temperature reduced the viscosity and density of the ionic liquids which facilitates TaF5 electroreduction, in particular, in [Py1,4]TFSA. A herringbone reconstruction of the Au electrode was observed by STM for both ionic liquids with and without TaF5. Ta deposition was proved by STM and EQCM in [Py1,4]TFSA. Cracked layers, with ionic liquid trapped inside, were obtained by direct plating from the [TFSA]- ionic liquid. No Ta containing deposits could be obtained in the liquid with the [FAP]- anion.