FIL or Fil may refer to:
- Functional Imaging Laboratory, the colloquial name for the Wellcome Trust Centre for Neuroimaging.
- International Luge Federation, the international governing body for the sport of luge.
- Federation of International Lacrosse, the international governing body for the sport of lacrosse.
- Fidelity International Limited, an international asset management and mutual fund company.
- FIL file (disambiguation), various computer file formats.
- Firestone Indy Lights, a developmental series that runs in conjunction with the IZOD IndyCar Series.
- Fil (milk product), or filmjölk, a Swedish fermented milk product.
- Sura Al-Fil, the 105th sura of the Qur'an.
- Fil de Cassons, a mountain in the Alps.
- Viili, a fermented milk product in Swedish
- Florida International League, a former minor league baseball circuit.
- The ISO 639 language code for the Filipino language
- The Guadalajara International Book Fair, better known as the FIL (from its Spanish name:Feria Internacional del Libro de Guadalajara) is the most important annual event of its kind in the Spanish-speaking world, and the second largest book fair in the world after Frankfurt's.