The eighth is the religion of the Báb and the remaining seven are: Hinduism, (Shoghi Effendi)
As regards religions….
There can be no doubt whatever that the peoples of the world, of whatever race or religion, derive their inspiration from one heavenly Source, and are the subjects of one God. All of them, except a few which are the outcome of human perversity, were ordained of God, and are a reflection of His Will and Purpose. (Baha’u’llah)
''The number nine, which in itself is the number of perfection, is considered by the Bahá'ís as sacred, because it is symbolic of the perfection of the Bahá'i Revelation which constitutes the ninth in the line of existing religions, the latest and fullest Revelation which mankind has ever known. The eighth is the religion of the Báb and the remaining seven are: Hinduism, Buddhism, Zoroastrianism, Judaism, Christianity, Islám, and the religion of the Sabaeans. These religions are not the only true religions that have appeared in the world but are the only ones still existing. Source: Bahá'i Reference Library - Directives from the Guardian, Pages 51-52