In tetralogy of Fallot (TOF), the most common form of cyanotic congenital heart disease, only a few patients reach adulthood without surgical correction. We present a case of a woman with TOF who was diagnosed at the age of 39 when she presented with features of congestive heart failure. The main factor contributing to her longevity included the slow development of her pulmonary artery stenosis together with left ventricular hypertrophy. Less than 3% of all patients with uncorrected TOF survive beyond their 40s but late operative repair is still a valuable option. This case provides an insight into the late outcome of an older patient with uncorrected TOF.