The present study depicts a spectroscopic investigation on the binding interaction of a phenazinium-based photosensitizer, phenosafranin (PSF) with a micelle forming surface active ionic liquid (SAIL), 1-butyl-3-methylimidazolium octyl sulfate (Bmim Os). The steady-state as well as time-resolved spectroscopic results reveals the binding of PSF with the micelles of the ionic liquid. The modulations of the spectral properties of PSF on interacting with Bmim Os micelles have been further employed to monitor the effect of various cyclodextrins, αCD, βCD and γCD (with varying dimensions of the hydrophobic cavity), on the Bmim Os micellar aggregates. The effective disruption of the Bmim Os micelles in presence of CDs is confirmed from the reduced size of Bmim Os micelles with added CD as observed from the DLS results. © 2018