In the present communication, the physicochemical properties between an anionic surface active ionic liquid (SAIL) 1-butyl-3-methylimidazolium dodecyl sulfate [C(4)mim][C12SO4] and nonionic polymers poly(vinylpyrrolidone) (PVP)/poly(ethylene glycol) (PEG) have been investigated by conductance and surface tension measurements. From these measurements the critical aggregation concentration (cac), critical micelle concentration (cmc), and degree of ionization (alpha) have been estimated. To understand the aggregation and interfacial behaviour of [C(4)mim][C12SO4] towards PVP and PEG, various thermodynamic and surface parameters have also been derived and discussed. The results exhibit that [C(4)mim][C12SO4] interacts strongly with PVP as compared to PEG.