Lightweight and conformable electroactive actuators stimulated by low electric fields are required for emerging responsive technologies. In this work, we demonstrate that selectively swollen triblock copolymers yield electroactive nanostructured polymers (ENPs) that exhibit excellent displacement (>200% areal strain) under an applied electric field (see figure). Such ENPs possess properties that can be broadly tailored and represent a viable avenue to designer organic actuators for advanced engineering, biomimetic, and biomedical applications.