Congenital branchial fistulas and cysts are an interesting subject in cervical pathology. There are congenital malformations with late expression in young adults that require correct diagnosis and appropriate treatment. We review essential notions of cervical embryology to understand the mechanism of occurrence of these malformations and their clinical expression. The most common cases present vestiges from the second branchial arch, with the appearance of a cystic tumor or a fistulous orifice on the anterior edge of the sternocleidomastoid muscle, at the level of the hyoid bone. Performant imagery is mandatory for appropriate diagnosis, so we recommend a cervical computed tomography (CT) scan or cervical magnetic resonance imaging (MRI) to evaluate the relations with great vessels of the neck or other lesions. The treatment implies complete surgical excision because otherwise there is a high risk of recurrence of the lesion. The differential diagnosis includes cystic lymphangioma, dermoid cyst, tuberculous adenopathy, cystic hygroma, lateral cervical cystic metastases. Histological examination is mandatory for a definite diagnosis. Also, there is a small percentage of malignancy of these malformations, but it is very important to check that all the histological diagnostic criteria for a primary branchiogenic carcinoma are accomplished. Therefore, although it is a benign cystic cervical pathology, the diagnosis and treatment must be made very accurately for a complete cure, and this review aims to summarize the current approach to branchial remnants of the neck.