B49

B49 or B-49 may refer to:
 * Bundesstraße 49, a German road
 * B49 (New York City bus) in Brooklyn in the United States
 * HLA-B49, an HLA-B serotype
 * A postcode area in Alcester, Warwickshire, England
 * Northrop YB-49, an American aircraft
 * B-49 (submarine), a Soviet Foxtrot class diesel-electric hunter-killer submarine
 * Persiaran Mokhtar Dahari, in Selangor, Malaysia