FOST

FOST may refer to:
 * Force océanique stratégique, the strategic submarine forces of the French Navy.
 * Flag Officer Sea Training (India) in the Indian Navy
 * Flag Officer Sea Training (Pakistan) in the Pakistani Navy
 * Flag Officer Sea Training (United Kingdom) in the Royal Navy (United Kingdom)
 * Future of StoryTelling, an annual summit

Fost may refer to:
 * Fošt, a settlement in northeastern Slovenia
 * Sant Fost de Campsentelles, a village in the province of Barcelona, Spain
 * Ingrid Föst (born 1934), a German gymnast