Congenital myopathies (CMyo) are a group of rare inherited muscle disorders classified to date according to myopathological features on muscle biopsy. They usually present with an early onset, with a slow or non‐progressive muscle weakness. The phenotypic spectrum is wide, ranging from severe early onset forms to milder and later onset conditions. Data regarding the disease trajectory of CMyo in adult patients are lacking. Here, we describe the clinical, myopathological, and genetic features of a large cohort of adult CMyo patients to facilitate their management in adulthood.