By simply blending two diblock copolymers with the same chemistry but with different compositions one is able to create well‐defined larger soft nanoparticles as well as bimodal soft nanoparticles. Specifically, blending two diblock copolymers in a solvent good for both blocks followed by a gradual introduction of a non‐solvent results in a mixed micelle, larger than their pure block‐copolymer‐forming micelles. The formation of well‐defined larger micelle is due to the balance between the ability of the mixed micelles to assemble or merge in comparison to their pure diblock copolymer micelles. Evidently, the blending ratio, the mixing protocol, and non‐solvent addition rate are crucial to achieving well‐defined larger or bimodal micelles.
