Swifties are the fandom of the American singer-songwriter Taylor Swift. Regarded by journalists as one of the largest and most devoted fanbases, Swifties are known for their high levels of participation, community, and cultural impact on the music industry and popular culture. They are a subject of widespread coverage in the mainstream media.

Critics have opined that Swift has redefined artist–fandom relationships by establishing an intimate connection with Swifties. She has frequently engaged with, helped, credited and prioritized her fans, who have offered unprecedented support and interest in her works irrespective of her wavering reception in the media. They continued to support Swift through her genre transitions, unanticipated artistic pivots, and her highly publicized controversies such as the 2019 masters dispute, while instigating the political scrutiny of Ticketmaster that led to the implementation of various laws and stimulating economic growth with the Eras Tour. Journalists consider Swifties as a significantly influential voting bloc, especially in the politics of the United States.

Swift's releases, promotional efforts, and fashion have garnered attention for incorporating Easter eggs and clues that are decoded by Swifties and considered part of her musical universe. On the other hand, some Swifties criticize Swift herself for her lifestyle and professional choices, which journalists disapprove as a parasocial relationship. Swifties are themselves a subject of criticism, as some fans display disregard for Swift's privacy, publicizing her real-time locations and verbally abusing individuals, including celebrities, who malign Swift. They were targetted in the 2024 Southport stabbings and Vienna terror plot. Cultural analyses have variably described Swifties as a community of interest, a subculture, and a near-metaverse, while academics have studied them for their consumerism, content creation, social capital, collective effervescence, organizing prolificacy, and interpersonal relationships. The word "Swiftie(s)" was added to the Oxford Dictionary of English in 2023.