Science and technology

Ultra (cryptography), the codename for cryptographic intelligence obtained from German signal traffic in World War II
Adobe Ultra, a vector-keying application
Sun Ultra series, a brand of computer workstations and servers
ULTRA (machine translation system), a machine translation system

Music

Ultra (British band), an English pop band
Ultra Music Festival, an annual electronic festival in Miami, Florida
Ultra Worldwide, a series of annual electronic music festivals each called Ultra
Ultra, a collaboration between two members of hip hop group Ultramagnetic MCs, who released the album Big Time
Ultra (music), a post-punk movement in the Netherlands
Ultra house, a music place in Handen, Sweden
Ultra Records, a record label

Ultra (Malaysia), a Malaysian group of racial extremists
ULTRA (UK agency), the Unrelated Live Transplant Regulatory Authority, a defunct UK government regulatory body
Ultra-royalists or Ultras, a reactionary group after Napoleon's defeat

Ultras, football fans renowned for ultra-fanatical support, sometimes to the point of violence
The ULTRA (University of Life Training and Recreational Arena), former name for the PhilSports Arena in Pasig, Philippines
Ultra Motorsports, a NASCAR team that ran from 1995–2005
Ultra running, endurance races at distances typically beyond marathon

Ultra (magazine), avant-garde Finnish-Swedish magazine in Finland
ULTra (rapid transit), a personal rapid transit system deployed at London Heathrow airport
Ultra (TV channel), a Serbian children's channel
Ultra Electronics, a British defence and aerospace company
Ultra Games, a subsidiary of Konami of America
Ultra-prominent peak, a mountain with a topographic prominence of at least 1,500 metres
Ultra Food & Drug, a defunct supermarket chain in Ontario, Canada
Ultra Distributors, a home video distribution company in India