We demonstrate sensitive detection of alpha protons of fully protonated proteins by solid‐state NMR spectroscopy with 100–111 kHz magic‐angle spinning (MAS). The excellent resolution in the Cα‐Hα plane is demonstrated for 5 proteins, including microcrystals, a sedimented complex, a capsid and amyloid fibrils. A set of 3D spectra based on a Cα–Hα detection block was developed and applied for the sequence‐specific backbone and aliphatic side‐chain resonance assignment using only 500 μg of sample. These developments accelerate structural studies of biomolecular assemblies available in submilligram quantities without the need of protein deuteration. No deuterium: With new 111 kHz magic‐angle spinning probes, high‐resolution 1H‐detected NMR spectroscopy of insoluble, crystalline, or self‐assembled protein aggregates is now feasible without replacing side‐chain protons with deuterons. α‐Protons become sensitive and spectrally resolved NMR probes, which allow backbone and side‐chain resonance assignment in about one week of experimental time for proteins of about 20 kDa.