HRT most commonly refers to:
- Gender-affirming hormone therapy, also known as hormone replacement therapy
- Masculinizing hormone therapy
- Feminizing hormone therapy
- Hormone replacement therapy, a treatment used to reduce symptoms associated with menopause
- Hostage Rescue Team, the FBI's elite tactical unit
HRT may also refer to:
Health and medicine
- Habit reversal training
- Heart rate turbulence
- Humane Research Trust, a British medical research charity
Motor racing
- HRT Formula 1 Team, a defunct racing team
- Haupt Racing Team, a German auto racing team
- Walkinshaw TWG Racing, an Australian motor racing team that previously traded as the Holden Racing Team
Transport
- Hampton Roads Transit, in the Norfolk-Virginia Beach, United States metro area
- Hartwell Railroad, in Georgia, United States
- Heavy rail transit, a term for types of passenger rail
- Helsinki Regional Transport Authority (Swedish: ')
- Hertfordshire Rail Tours, a defunct British railway company
- Hiroshima Rapid Transit, in Japan
- Honolulu Rail Transit, now known as the Skyline, a light metro in Hawaii
- Hurlburt Field, a United States Air Force field in Florida, United States
- RAF Linton-on-Ouse, a Royal Air Force station in England (IATA code: HRT)
Other uses
- Hard real-time, in computing
- Hértevin language, spoken in Turkey
- Hertfordshire, county in England, Chapman code
- High rising terminal, a feature of speech
- Hrvatska radiotelevizija, Croatia's national broadcaster
- Hudson River Trading, an American trading firm
- Hydraulic retention time, in hydrology
- Horse Race Tests, viral Twitter videos