[6] The Standard Oil Building was one of several corporate headquarters to be constructed at the southern end of Broadway during the early 20th century.

[12] The Beaver Street light court was the last section to be constructed due to the presence of a holdout lot occupied by Childs Restaurants.

[17][20] The tower section of 26 Broadway contains an additional 13 stories above the northern edge of the expanded base, above which is a stepped triple-height pyramid.

[12] The modern building's facade is primarily composed of buff-colored Indiana Limestone, covering the tower and much of the base.

[19][16] The main entrance is near the middle of the curved Broadway facade; it consists of a recessed double-height arch, with elaborately carved spandrels at its top.

[21] Above the base, the Broadway facade rises as a twelve-story wall resembling a cliff; it is interrupted only by a setback from the Beaver Street side, where there is an intermediate cornice.

The buildings were occupied by numerous tenants, who were allowed to temporarily stay in place due to the dearth of office space in Lower Manhattan in the 1920s.

[12] A cofferdam wall was built underneath part of the expanded site, extending down to the bedrock at the deepest level.

[14] The use of columns, pilasters, rusticated walls, and heavy staircases and doorways was intended to create the effect of "a princely palace or merchant's mansion".

When the building was completed, each story also had its own fire alarm station and watchman's tower, as well as bronze-framed directory signs.

[14][38][39] The boardroom covered 2,000 square feet (190 m2) and contained a double-height ceiling with relief panels; a limestone fireplace; and oak wainscoting.

[40] Next to it was an anteroom with carved oak pilasters, frieze, and moldings, as well as a plaster ceiling and Kato stone wall.

[14] Private offices extended south and east of the 21st-story boardroom and had walnut walls, plaster ceilings, Siena marble fireplaces, and cork floors covered with carpets.

[17][20][33] The site of the Standard Oil Building was occupied by Dutch houses after the colony of New Amsterdam was founded in the 17th century.

[44] Starting in the early 19th century, when New York City became a nationally prominent commercial hub, many firms chose to build their headquarters in Lower Manhattan, renting the unused space to subsidiaries or other companies.

[22] By 1884, the company had acquired lots at 24-28 Broadway near Bowling Green, and had started erecting a headquarters building at the site.

[4][22][46] It was designed by Ebenezer L. Roberts with a Renaissance Revival granite facade, and had a flat roof above the ninth floor, as well as a central bay that rose an additional story.

[50] This did not resolve the monopoly concerns: The New York Times in 1906 said that "every cent of [Standard Oil's subsidiaries] made found its way to 26 Broadway".

[55] The building ultimately served as the headquarters of the Standard Oil Company of New York (Socony, later Mobil) once the split was completed.

[5] After World War I, Standard Oil president Walter C. Teagle decided to greatly expand the structure by buying the neighboring buildings on the block.

[58][b] In August 1920, Carrère and Hastings filed plans with the New York City Department of Buildings for enlarging 26 Broadway to 24 stories, plus a three-story pyramidal roof.

[4] Thomas Hastings—the only living partner of Carrère and Hastings, who had helped design the Cunard Building across the street—was chosen as lead architect.

[61] Construction was complicated by the Childs Restaurants location's decision to hold out until its lease expired; the difficulty of evicting the four buildings' occupants; and a dearth of available office space in the neighborhood.

[22] As a result, the expansion was undertaken in four phases,[61][22][26][47] and the plans were changed in 1921 to allow for a light court around the location of the restaurant, rather than a bulky base as first projected.

[22][26] Two tenants could not relocate before the construction was scheduled to start, so engineers began demolishing one building while underpinning the neighboring structure.

[63][67] The same year, Standard Oil of New Jersey (by that time, also known phonetically as Esso) announced its intention to consolidate its operations at Rockefeller Center, although it retained other offices at 26 Broadway.

[79] The Museum of American Finance (MOAF) was founded in the building in 1988, initially occupying 250 square feet (23 m2) of space on the ground floor.

[96] As of 2020[update], tenants include Cornell University's College of Architecture, Art, and Planning,[87][97] Olo,[87][98] SecondMarket, SpeechCycle, and JDRF.

[27] As the building was completed, architectural critics praised the design of 26 Broadway as having more emphasis on its form instead of the articulation of windows and other details.

[66] In a book about the work of Carrère and Hastings, Mark Hewitt wrote that 26 Broadway was "one of the supreme accomplishments of American Classicism".