Intermolecular interactions stabilising the CAL1–CENP-A/H4 complex were analysed using chemical Cross-Linking Mass Spectrometry (CLMS). Purified recombinant CAL11-160–CENP-A101-225–H4 complex was crosslinked using EDC and BS3. The crosslinked peptides were analysed by mass spectrometry to identify intra- and intermolecular contacts. Notably, the data revealed several intramolecular crosslinks between the N- and C-terminal regions of CAL11-160, suggesting a direct interaction between these regions.