ULF can refer to:

• Ultra low frequency, the radio frequency band from 300 Hz to 3 kHz
• Ultra Large Format, used for cameras producing negatives larger than 8" x 10"
• Ultra Low Floor, is a type of tram
• United Labour Front, a defunct political party in Trinidad and Tobago
• United Liberation Front of Asom, a militant group
• Ulf (name), a common first name in Scandinavia and Europe, meaning wolf

• Ulf Jarl, Danish earl

• Ulf Kirsten, former German/East German and Bayer Leverkusen football (soccer) striker

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