AbstractBright red emission (620–650 nm) from perovskite light‐emitting diodes (PeLEDs) is usually achieved via a composition including both bromine and iodine anions, which results in poor performance and stability due to phase separation under operating conditions. Here a large‐scale ligand‐assisted reprecipitation method is devised with nonpolar solvent that enables the fabrication of CsPbI3 nanowire clusters, emitting at 600 nm. The blue‐shift of this emission relative to that of bulk CsPbI3 (≈700 nm) is attributed to quantum confinement in nanowires. The growth of the nanowires is along the [011] crystal direction and is vacancy driven, resulting in the healing of surface defects and thereby a high photoluminescence quantum yield of 91%. The clusters with ultralow trap density show remarkable structural and environmental stability. PeLEDs based on these clusters exhibit an external quantum efficiency of 6.2% with Commission Internationale de l'Eclairage coordinates of (0.66, 0.34), and record luminance of 13 644 cd m−2 of red electroluminescence. The half‐lifetime under an accelerated stability test is 13.5 min for an unencapsulated device in ambient conditions operating at an initial luminance of 11 500 cd m−2, which corresponds to an estimated half‐lifetime of 694 h at 100 cd m−2 based on acceleration factor obtained by experimental testing.