Functionalizing polymersomes remains a challenge due to the limitation in reaction conditions applicable to the chemistry on the surface, hindering their application for selective targeting. In order to overcome this limitation, functionalization can be introduced right before the self-assembly. Here, we have synthesized a library (32 examples) of PEG-b-PS and PEG-b-PDLLA with various functional groups derived from the amine-functionalized polymers, leading to functionally active polymersomes. We show that polymersome formation is possible via the general method with all functionalized groups and that these handles are present on the surface and are able to undergo reactions. Additionally, this methodology provides a general synthetic tool to tailor the functional group of the polymersome right before self-assembly, without limitation on the reaction conditions.