CoreSite Realty Corporation (NYSE: COR), a national provider of powerful, network-rich data centers, today announced the income tax allocation for federal income tax purposes of its 2012 distributions on its common stock (CUSIP: 21870Q105).

Record Date   Payable Date   Distribution Per Share   Taxable Ordinary Dividends   Long-term Capital Gains   Long-term Unrecaptured Section 1250 Gain   Qualified Dividends   Return of Capital
 
3/30/2012 4/16/2012 $ 0.18 $ 0.18 $ 0.00 $ 0.00 $ 0.00 $ 0.00
6/29/2012 7/16/2012 0.18 0.18 0.00 0.00 0.00 0.00
9/28/2012 10/15/2012 0.18 0.18 0.00 0.00 0.00 0.00
12/31/2012 1/15/2013   0.27   0.27   0.00   0.00   0.00   0.00
Total $ 0.81 $ 0.81 $ 0.00 $ 0.00 $ 0.00 $ 0.00

Under the tax rules applicable to real estate investment trusts such as CoreSite, the entire amount of the January 15, 2013, distribution applies to tax year 2012.

CoreSite's tax return for the year ended December 31, 2012, has not been filed. As a result, the income tax allocation for the distributions discussed above has been calculated using the best available information as of the date of the release.

Please note that federal tax laws affect taxpayers differently, and the information in this release is not intended as advice to shareholders on how distributions should be reported on their tax returns. Also note that state and local taxation of real estate investment trust distributions varies and may not be the same as the taxation under the federal rules. CoreSite encourages shareholders to consult with their own tax advisors as to their specific federal, state, and local income tax treatment of CoreSite distributions.

About CoreSite

CoreSite Realty Corporation (NYSE: COR) is the data center provider chosen by more than 750 of the world's leading carriers and mobile operators, content and cloud providers, media and entertainment companies, and global enterprises to run their performance-sensitive applications and to connect and do business. CoreSite propels customer growth and long-term competitive advantage through the CoreSite Mesh by connecting the Internet, private networking, mobility, and cloud communities within and across its 14 high-performance data center campuses in nine markets in North America. With direct access to 275+ carriers and ISPs, over 180 leading cloud and IT service providers, inter-site connectivity, and the nation's first Open Cloud Exchange that provides access to thousands of lit buildings and multiple key cloud on-ramps, CoreSite provides easy, efficient and valuable gateways to global business opportunities. For more information, visit www.CoreSite.com.

CoreSite Investor Relations Contact
+1 303.222.7276
InvestorRelations@CoreSite.com
or
CoreSite Media Contact
Jeannie Zaemes | CoreSite Marketing Senior Director
+1 720.446.2006 | +1 866.777.CORE
Jeannie.Zaemes@CoreSite.com