Cult is a term, considered pejorative by some, for a relatively small group which is typically led by a charismatic and self-appointed leader, who excessively controls its members, requiring unwavering devotion to a set of acts and practices which are considered deviant(outside the norms of society).[1] This term is also used for a new religious movement or other social group which is defined by its unusual religious, spiritual, or philosophicalbeliefs and rituals,[2] or its common interest in a particular personality, object, or goal.
Religion is a range of social-cultural systems, including designated behaviors and practices, morals, beliefs, worldviews, texts, sanctified places, prophecies, ethics, or organizations, that generally relate humanity to supernatural, transcendental, and spiritual elements[1]—although there is no scholarly consensus over what precisely constitutes a religion.[2][3]Different religions may or may not contain various elements ranging from the divine,[4]sacredness,[5] faith,[6] and a supernatural being or beings.[7]
Religious symbols: Christianity, Islam, Isese, Hinduism, Judaism, Baha'i, Eckankar, Buddhism, Jainism, Wicca, Unitarian Universalism, Sikhism, Taoism, Thelema, Tenrikyo, Shinto
Religious practices may include rituals, sermons, commemoration or veneration (of deities or saints), sacrifices, festivals, feasts, trances, initiations, matrimonial and funeraryservices, meditation, prayer, music, art, danceor public service. Religions have sacred histories and narratives, which may be preserved in sacred texts, symbols and holy places, that primarily aim to give life meaning. Religions may contain symbolic tales that may attempt to explain the origin of life, the universe, and other phenomena; some followers believe these to be true stories. Traditionally, both faith and reason have been considered sources of religious beliefs.[8]
a quick look on wiki would answer your question
In reality the difference lies in wide spread acceptance. Although the use of the word cult is often used in a damning sense. It would indicate a questionable leader with people blindly following harmful practices. In my experience this is far removed from many in mainstream religious groups who do a lot of questioning