S33

S33 may refer to:

Aviation

• Blériot-SPAD S.33, a French airliner
• Letov Š-33, a Czechoslovak bomber
• Madras Municipal Airport, in Jefferson County, Oregon, United States
• Short S.33, a British flying boat
• Sikorsky S-33 Messenger, an American sesquiplane
• Spectrum S-33 Independence, an American business jet

Naval vessels

• Brazilian submarine Tapajó (S-33)
• SMS S33 (1914), a torpedo boat of the Imperial German Navy
• Spanish submarine Narcíso Monturiol (S33)
• USS S-33 (SS-138), a submarine of the United States Navy

Other uses

• S33 (Long Island bus)
• S33 (ZVV), a line of the Zürich S-Bahn
• County Route S33 (Bergen County, New Jersey)
• S33: Take precautionary measures against static discharges, a safety phrase
• Section 33 of the Canadian Charter of Rights and Freedoms
• Sotho language
• Sulfur-33, an isotope of sulfur
• S33, a postcode district in the Hope Valley, Derbyshire, England