The One North LaSalle Building or One LaSalle Street Building is a building in the LaSalle Street corridor in the Loop community area of Chicago managed by MB Real Estate. It was for some time one of Chicago's tallest buildings. Built in 1930 by architects Vitzthum & Burns, it replaces the Tacoma Building by Holabird & Roche. The building is located across Madison Street from Roanoke Building. It was designated a Chicago Landmark on April 16, 1996, and added to the National Register of Historic Places on November 22, 1999. Its 5th floor relief panels depict the explorations of René-Robert Cavelier, Sieur de La Salle.

One LaSalle Street Building
U.S. National Register of Historic Places
Chicago Landmark
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Location	1 N. LaSalle Street Chicago, Illinois
Coordinates	41°52′55.37″N 87°37′55.68″W / 41.8820472°N 87.6321333°W / 41.8820472; -87.6321333
Built	1930
Architect	Vitzthum, Karl Martin; Burns, John J.
Architectural style	Skyscraper, Art Deco
NRHP reference No.	99001378
Significant dates
Added to NRHP	November 22, 1999
Designated CL	April 16, 1996.<

The Chicago Board of Trade Building was the tallest building in Chicago for some 35 years by conventional definitions. At 530 feet (160 m) and 48 stories, One North LaSalle was the fourth tallest building (fifth tallest after the completion of the LaSalle National Bank Building) structure for approximately the same period. Other sources, however, claim this building was the tallest structure for approximately the same period defined by excluding items on top of the main building such as the Board of Trade Building's statue and pyramidal top, the steeple of the Chicago Temple Building, the pyramidal top of the Pittsfield Building, and the mansard roof of the Civic Opera House. The height differences are easily seen in scale depictions.