Defective ion channel turnover and clearance of damaged proteins are associated with aging and neurodegeneration. The L-type CaV1.2 voltage-gated calcium channel mediate depolarization-induced calcium signals in heart and brain. Here, we determined the interaction surface between the L-type calcium channel CaVβ subunit and actin using cross-linking mass spectrometry and protein-protein docking, and uncovered a role in replenishing damaged CaV1.2 channels. Computational and in vitro mutagenesis identified hotspots in CaVβ that decrease its affinity for actin but not for CaV1.2. Coexpression of an actin-association-deficient CaVβ mutant with the CaV1.2 channel downregulated current amplitudes with a concomitant reduction in the number of functionally available channels. Neither alterations in the single-channel properties nor changes in the total number of channels at the cell surface were found, indicating that current inhibition resulted from a build-up of conduction-defective channels. Our findings established CaVβ–actin interaction as a key player for selective monitoring and clearing corrupted CaV proteins to ensure the maintenance of a functional pool of channels and proper calcium signal transduction. The CaVβ–actin molecular model introduces a potentially druggable protein-protein interface to intervene CaV-mediated signaling processes.