Mitochondrial transporter that mediates choline import across the inner mitochondrial membrane, thereby regulating mitochondrial choline levels and downstream metabolism, including betaine and purine nucleotide synthesis (PubMed:39111307, PubMed:38977856, PubMed:39084256). Plays a key role in mitochondrial respiration, brown fat thermogenesis, and the maintenance of mitochondrial membrane integrity (By similarity). {ECO:0000250|UniProtKB:Q8BW66, ECO:0000269|PubMed:38977856, ECO:0000269|PubMed:39084256, ECO:0000269|PubMed:39111307}. This is the function of SLC25A48 (solute carrier family 25 member 48, Ensembl gene identifier ENSG00000145832).