S27

S27 may refer to:

• S27 (Long Island bus)
• S27: Take off immediately all contaminated clothing, a safety phrase in chemistry
• Blériot-SPAD S.27, a 1919 small French airliner
• British NVC community S27, a swamps and tall-herb fens community in the British National Vegetation Classification system
• County Route S27 (California)
• Short S.27 and its derivatives the Improved S.27 series, a British biplanes of the 1910–1912 period used by the Royal Navy and Royal Naval Air Service
• USS S-27 (SS-132), a 1920 S-class submarine of the United States Navy
• a Munich S-Bahn line