Intrauterine contraceptive devices (IUCDs) are a common form of reversible contraception owing to fewer systemic side effects and low cost, especially in a developing country like India. However, IUCDs are not without complications. Migration of a device into adjacent organs is the most morbid of all the documented complications. A patient who presents with a history that suggests loss or disappearance of an IUCD thread associated with urinary symptoms should raise suspicions that a device may have migrated into the bladder. Physicians should also be aware of possible secondary vesical calculus formation. Further radiological investigations and appropriate management are warranted. We present a case report describing the migration of an IUCD into the bladder with secondary calculus formation.