NEW YORK—Tenants at the Empire State Building have two new on-site amenities available to them: a conference center and a tenants-only fitness center.

“The conference and fitness centers are part of our master plan to create an in-building campus environment with a full range of on-site amenities for our tenants,” said Anthony Malkin, president of Malkin Holdings, which supervises the property.

Upon completion, which is anticipated in March 2013, the new conference center will include 3,236 sq. ft. of space and will be housed on the 67th floor.

In addition, the 14,500-sq.-ft. fitness center, slated to open in the fourth quarter of this year, will be located on the building’s concourse level.

The Empire State Building has undergone more than $550 million in energy-efficiency upgrades, including infrastructure upgrades, lobby and public area upgrades. The property has earned Energy Star designation and also earned LEED-EB Gold certification from the U.S. Green Building Council.