High‐efficiency pure blue phosphorescent organic light‐emitting diodes (OLEDs) remain one of the grand challenges, principally because the emissive complexes employed either do not possess sufficiently high photoluminescence quantum yields or exhibit unsatisfactory Commission International de l'Éclairage (CIE) coordinates. Here two deep‐blue‐emitting homoleptic iridium(III) complexes are reported and OLEDs are demonstrated with CIE coordinates of (0.15, 0.05) and maximum external quantum efficiency of 13.4%, which decreases slightly to 12.5% at 100 cd m−2. They represent examples of the most efficient OLEDs surpassing the CIEy requirement of the National Television System Committee (NTSC) and the European Broadcasting Union (EBU). Emitter orientation contributes to the excellent device performance. By studying two isomeric homoleptic iridium(III) complexes containing N‐heterocyclic carbene ligands, exceptional organic light‐emitting diode performance is demonstrated with efficiency of 12.5% at display‐relevant brightness of 100 cd m‐2, and deep blue color corresponding to Commission International de l'Éclairage (CIE) coordinates of (0.154, 0.052). The device performance is complemented by a thorough computational, optoelectronic, and emitter orientation analysis.