Background: During cleft palate repair, mucoperiosteal flaps are elevated from the palatal shelves and the nasal septum to accomplish tension-free closure of the nasal floor. This study was designed to geometrically describe how palate repair inherently limits airflow by decreasing nasal cavity cross-sectional area and increasing nasal airflow resistance. In addition, this study investigates whether the width of the repaired cleft palate directly affects the degree of postoperative airflow resistance. Methods: A simplified geometric model of normal nasal cavity anatomy was compared with an equivalent schematic representing an individual with an unrepaired palatal cleft. Mathematical equations approximating the cross-sectional areas of normal and cleft nasal cavities were created. The theoretical postoperative loss of nasal cavity cross-sectional area was then considered for both unilateral and bilateral palatal clefts. Results: According to this geometric model, the cross-sectional area of the nasal cavity is decreased in patients who undergo cleft repair. Repaired bilateral clefts experience a greater area loss than their unilateral counterparts. Conclusion: Nasal cavity resistance is higher in patients who have undergone cleft repair than in individuals who have not undergone cleft repair. because tension-free closure of the nasal floor inherently reduces cross-sectional breathing area. The wider the cleft, the higher the resistance to nasal airflow postoperatively. This iatrogenic source of nasal resistance is likely additive to other anatomic contributors to airflow resistance observed in individuals with cleft nasal deformities.