S44 may refer to: Transport S44 (New York City bus), serving Staten Island, United States S44 (St. Gallen S-Bahn), a railway service in Switzerland S44, a line of the Lucerne S-Bahn in Switzerland GER Class S44, a British steam locomotive New Jersey Route 324, designated Route S44 until 1953
Navy , a submarine of the Indian Navy , a submarine of the United States Navy
Other uses Sulfur-44, an isotope of sulfur S44, a postcode district in Chesterfield, England