Tuberous sclerosis complex (TSC) is an autosomal dominantly inherited disorder with variable expressivity associated with hamartomatous tumors, abnormalities of the skin, and neurologic problems including seizures, intellectual disability, and autism. TSC is caused by pathogenic variants in eitherTSC1orTSC2. In general,TSC2pathogenic variants are associated with a more severe phenotype thanTSC1pathogenic variants. Here, we report a pathogenicTSC2variant, c.1864C>T, p.(Arg622Trp), associated with a mild phenotype, with most carriers meeting fewer than two major clinical diagnostic criteria for TSC. This finding has significant implications for counseling patients regarding prognosis. More patient data are required before changing the surveillance recommendations for patients with the reported variant. However, consideration should be given to tailoring surveillance recommendations for all pathogenicTSC1andTSC2variants with documented milder clinical sequelae.