Blair House usually refers to
Blair House, Washington, D.C.
or it may refer to (with variations including "Estate" and "Ranch"):
Combellack-Blair House, Placerville, California, NRHP-listed Powell and Blair Stone Ranch, Proctor, Colorado, NRHP-listed in Logan County William McCormick Blair Estate, Lake Bluff, Illinois, NRHP-listed in Lake County Blair-Dunning House, Bloomington, Indiana, NRHP-listed Blair House (Washington, Iowa), NRHP-listed Blair Flats, St. Paul, Minnesota, NRHP-listed Blair Farm, Boone, North Carolina, NRHP-listed in Watauga County William Allen Blair House, Winston-Salem, North Carolina, NRHP-listed in Forsyth County Herbert S. Blair House, Bucyrus, Ohio, NRHP-listed in Crawford County Blair House (Montgomery, Ohio), NRHP-listed, NRHP-listed Sen. William Blair House, Waukesha, Wisconsin, NRHP-listed in Waukesha County Quintin Blair House, Cody, Wyoming, NRHP-listed Charles E. Blair House, Laramie, Wyoming, NRHP-listed in Albany County
See also Blair-Rutland Building, Decatur, Georgia, NRHP-listed in DeKalb County