To assess the potential for cross-protective immunity conferred by prior exposure to common human coronaviruses (i.e., HKU1, OC43, NL63, and 229E), we next sought to characterize the conservation of the SARS-CoV-2 proteome across diverse coronavirus subgenera to identify highly conserved linear epitopes. After aligning reference proteome sequence data for 5 essential viral components (ORF1ab, S, E, M, and N proteins) across 34 distinct alpha- and betacoronaviruses, including all known human coronaviruses, we identified 48 highly conserved amino acid sequence spans (see Data File S1 in the supplemental material). Acknowledging the challenges to inferring cross-protective immunity among closely related peptides, we confined our attention exclusively to identical peptide matches. Among the conserved sequences, 44 SARS-CoV-2 sequences would each be anticipated to generate at least one 8- to 12-mer linear peptide epitope also present within at least one other common human coronavirus (Fig. 2; see also Table S2). In total, 564 such 8- to 12-mer peptides were found to share 100% identity with corresponding OC43, HKU1, NL63, and 229E sequences (467, 460, 179, and 157 peptides, respectively) (Table S3).