We derive a complementary cosmological upper bound on the fraction of dark matter residing inside nonaccreting massive compact halo objects (MACHOs) using the cosmic dawn and dark ages global 21-cm signal ($T_{21}$). MACHOs of mass $M\gtrsim {10}^3{M}_{\odot }$ moving through the baryonic fluid during postrecombination transfer kinetic energy to the intergalactic medium via dynamical friction, thereby raising the gas temperature and distorting the 21-cm signal predicted in the $\mathrm{\Lambda }$ cold dark matter framework. We consider both a monochromatic distribution of MACHOs and two extended mass distributions: log-normal and critical collapse. Imposing the conditions that the deviation in the global 21-cm signal $\mathrm{\Delta }{T}_{21}$ does not exceed 50 mK at $z\sim 17$ or 15 mK at $z\sim 89$, and that no emission signal appears at $z\gtrsim 300$, we derive upper bounds on the MACHO fraction $f_M$ across the mass range ${10}^3\lesssim M_c/M_{\odot }\lesssim {10}^7$. The dark ages and $z\gtrsim 300$ criterion yield constraints that are both tighter and free from astrophysical uncertainties associated with star formation, particularly $f_M=0.03$ for $M_c={10}^7{M}_{\odot }$, providing a complementary cosmological window. The extended mass distributions yield bounds that are less stringent than those of their monochromatic counterparts.

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• Cosmic microwave background
• Cosmology
• Massive compact halo objects