Chicago Architecture Info

300 East Randolph


Construction Photographs


Formerly The Blue Cross and Blue Shield of Illinois Building
Also known as The BCBS Tower
Address 300 East Randolph Street, Chicago, Illinois 60601
Neighborhood The Loop
Architecture firms
  • Original building: Lohan Associates
  • Vertical addition: Goettsch Partners
  • Office
  • Skyscraper
  • 1997: 33
  • 2009: 57
  • 1997: 411 feet
  • 2009: 796 feet
Floor space
  • 1997: 1,400,000 square feet
  • 2009: 2,300,000 square feet


  • Like a good number of buildings in downtown Chicago, this one was originally constructed with a vertical expansion in mind. When this building was completed in 1997, it was 33 stories tall. An additional 24 stories were added a decade later.
  • The vertical expansion of this building did not require city approval because approval for the original building (Phase 1), and the expansion (Phase 2) were granted at the time of the buildingʼs original construction.


2003 The managers of this building were asked to illuminate its Grant Park-facing Windows to spell out the name Shania Twain because she was playing a concert in the park. The request was denied.
July, 2006 Plans to add 24 stories to this building were announced.
October, 2007 A pair of cranes were put in place at the roof line to facilitate the vertical expansion.
November, 2009 The vertical expansion was completed.


For years this building provided a dignified presence on the edge of the railroad yard that would eventually be decked over to become Millennium Park. It looked out over Grant Park and the Loop with its blue glass and white accents reminding the office workers of the wonders of the great lake that lay just beyond. That placid harmony with its surroundings was shattered in 2007. On purpose.

Many buildings in Chicago aspire to reach higher than they do. This is one that actually attained its goal. In 2007 a project was started to add another 24 stories of offices on top of the 33 already built. The skyscraper was designed from the start for this kind of expansion. Blue Cross and Blue Shield of Illinois knew it would eventually be necessary. But the details were little more than a footnote in an archive, or a bit of trivia on a skyscraper nerdʼs web site for a decade.

The vertical extension cost $270,000,000 — a little over $10 million per floor — and was more than a little complicated. First, a small derrick was brought to the roof piece-by-piece. Once installed, it was used to lift up the pieces of a larger derrick that was assembled on the roof. The larger machine was then used to disassemble the smaller one and lower it back to the ground. When that was done, the remaining derrick was used to lift the pieces of a crane to the roof where it was assembled. The derrick was then moved and used to bring up a second crane.

It is remarkable that the upward expansion was needed so soon. Other buildings in the area have waited for decades, ready to be expanded.

At the time the original building was completed, it was a stately presence on East Randolph Street. But as the world progressed around it, the tower became less and less prominent. The final insult came with the 2007 completion of 340 On The Park, a 64-story residential tower next door that was double the size of the this building. Adding another 24 stories didnʼt bring this skyscraper head and shoulders above the its neighbors, but at least it no longer looked like the runt of the litter.

The best views of this building are actually from the back. And at night. This is how you can appreciate the structure of the building. It features a massive central atrium that is clearly visible through the glass when office lights illuminate it from within. You can sit in Lake Shore Park and watch the internal elevators whiz up and down the edges of the atrium serving the workers toiling long into the night. That atrium is surrounded on three sides by banks of offices. The arrangement is similar to the classic light well common in many Chicago buildings built around the turn of the 20th century. People in the offices are able to get light from all sides, even if they are deep within the center of the structure.

Stacking diagram

Level 57 Mechanical
Level 56 Mechanical
Level 55 Mechanical
Level 54 Office
Level 53 Office
Level 52 Office
Level 51 Office
Level 50 Office
Level 49 Office
Level 48 Office
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Level 46 Office
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Level 44 Office
Level 43 Office
Level 42 Office
Level 41 Office
Level 40 Office
Level 39 Office
Level 38 Office
Level 37 Office
Level 36 Office
Level 35 Office
Level 34 Office
Level 33 Office
Level 32 Mechanical
Level 31 Mechanical
Level 30 Office
Level 29 Office
Level 28 Office
Level 27 Office
Level 26 Office
Level 25 Office
Level 24 Office
Level 23 Office
Level 22 Office
Level 21 Office
Level 20 Office
Level 19 Office
Level 18 Office
Level 17 Office
Level 16 Office
Level 15 Office
Level 14 Office
Level 13 Office
Level 12 Office
Level 11 Office
Level 10 Office
Level 9 Office
Level 8 Office
Level 7 Office
Level 6 Office
Level 5 Office
Level 4 Office
Level 3 Office
Level 2 Lobby Office
Level 1 Lobby
Level B1 Lobby Transportation
Level B2 Parking Mechanical
Level B3 Parking Mechanical