Poly(2-oxazoline)s (POx) represent a versatile class of polymers synthesized via a living cationic ring-opening polymerization (CROP). This living nature allows for precise control over molar mass, dispersity, and end-group functionality. One common method for end-capping the CROP is through termination with nucleophiles such as sodium azide, which introduces an azide end-group suitable for further click chemistry modifications. However, the functionalization of, in particular, hydrophobic POx with azide end groups for bioconjugation has posed significant synthetic challenges. Herein, we report the development of a novel initiator system for the CROP of 2-oxazolines that enables the direct incorporation of azide functionality at the α-terminus of various POx derivatives. This approach overcomes previous limitations in quenching reactions of hydrophobic POx variants and provides consistently high end group fidelity across a spectrum of POx hydrophilicity. Polymers with an azide end group exhibited excellent reactivity in azide-alkyne cycloaddition reactions.