Originally called One Pennsylvania Plaza when plans for the building were announced in 2001, the Comcast Center went through two redesigns before construction began in 2005.

The building is named after its lead tenant, cable company Comcast, which makes the skyscraper its corporate headquarters.

Eventually the developer settled on the location where he constructed this building, a 2-acre (8,100 m2), $288 per square-foot parcel owned by Equitable Life Assurance Co.[9] In 2000, the architect and Driehaus Prize winner Robert A. M. Stern began working on a design for a skyscraper being planned by Liberty Property Trust in Philadelphia.

Anticipated US$400 million, One Pennsylvania Plaza was to be 750 ft (230 m) and made of kasota stone similar to the Philadelphia Museum of Art.

[11] Cable company Comcast had been looking for possible new headquarters space in anticipation of the end of its lease in Centre Square in 2006.

The redesign turned One Pennsylvania Plaza into a 60-story, 962 feet (293 m) tower, making it the tallest building in the city at the time.

[17] Liberty Property Trust hoped to get the One Pennsylvania Plaza site designated a Keystone Opportunity Improvement Zone (KOZ).

KOZ designation was intended to encourage development in poor, blighted areas by exempting the tenants of the building from all state and local taxes.

However, other Center City building owners, including Comcast's landlord at Centre Square, HRPT Properties Trust, were opposed to the plan.

[16][18] Both sides of the issue hired law firms, lobbyists, and business associates to promote their positions to city and state officials.

[20] In contrast, a report issued by a consulting company hired by Liberty Property Trust said that a KOZ designation for the skyscraper could generate US$27 million for the city.

Critics of the KOZ designation also claimed that close relationships between Liberty Property Trust and Comcast and the Rendell administration were inappropriately influencing the governor's position on the issue.

[22] The groundbreaking also featured Kodo, the Germantown High School drumline, and a 6-foot-tall (1.8 m) ice sculpture of the Comcast Center.

[11][23] While under construction, in March 2006, Liberty Property Trust negotiated with Philadelphia's Plumbers Union Local 690, which had issues with the building's waterless urinals.

The waterless urinals were part of the plan to make the Comcast Center an environmentally friendly building because they would save an extra 1.6 million US gallons (6,100 m3) of water a year.

Piping that would allow water to flow to the urinals in case they needed to be converted was installed in the Comcast Center, which Liberty Property Trust says was always part of the building's plan.

The deal completed Liberty Property Trust's planned recapitalization of the anticipated cost of the building, and the value of the joint venture, called Liberty/Commerz 1701 JFK Boulevard L.P., included mortgage debt and equity.

The ceremony, which was held in the building's future plaza, featured the raising of a steel beam to the skyscraper's highest point.

Along each floor, the corner spandrel panels feature upward and downward-facing 4,100K LEDs to create the appearance that the length of the building has been bottom-lit by spotlights.

The only major consistently active color element can be found at the top of the tuned mass damper; a single row of color-changing LEDs that is programmed to commemorate special events.

[44][45] The installation, designed and produced by Niles Creative Group, premiered on June 6, 2008, and runs eighteen hours each day.

The content of the video includes panoramic views of Philadelphia historic sites, images of space, dancers, acrobats and actors moving around a background designed to mimic wood paneling of the walls of the lobby.

Another part of the installation displays images of cranes and machinery forming the design of a clock that tells the correct time of day.

Other designs include a glass and stainless steel staircase that wraps around a four-story column of flat-screen monitors and connects the executive floors.

[42] Table 31, which had a cafe on the plaza and a restaurant spread over three floors in the tower, was owned by Philadelphia restaurateurs and chefs Georges Perrier and Chris Scarduzio.