Abstract: A new and distinct cultivar of Hydrangea plant named ‘SMNHMC’, characterized by its relatively compact, upright and outwardly spreading plant habit; vigorous growth habit; strong and sturdy stems; dark green-colored leaves; freely and remontant flowering habit with numerous panicles per plant; large mophead inflorescences with semi-double sterile flowers that are light purplish pink in color; and good garden performance.