Tha or THA may refer to:
- Temporary Housing Area
- Tetrahydroaminoacridine or Tacrine
- Texas Heartbeat Act
- Tha language, an Adamawa language of Nigeria
- Tha (Javanese) (ꦛ), a syllable
- Ṭha (Indic) a letter of Indic abugidas
- Tha (film), India
- Tha, a track by Aphex Twin on Selected Ambient Works 85–92
- THA, the IATA code for Tullahoma Regional Airport in the state of Tennessee, US
- THA, the ICAO code for Thai Airways International
- tha, the ISO 639-3 code for the Thai language
- THA, the National Rail code for Thatcham railway station in the county of Berkshire, UK
- Tobago House of Assembly, legislative body
- Total hip arthroplasty or hip replacement
- Transvaal Horse Artillery
- Troy Housing Authority, an agency of Troy, New York that subsidizes public housing