Exhibit 99.1

Piedmont Office Realty Trust Reports Fourth Quarter Results

- Provides 2011 Guidance -

ATLANTA, February 10, 2011 — Piedmont Office Realty Trust, Inc. (“Piedmont” or the “Company”) (NYSE:PDM), an owner of primarily Class A properties located predominantly in the ten largest U.S. office markets, today announced its results for the quarter and year ended December 31, 2010.

Highlights for the Three Months and the Year Ended December 31, 2010:

Donald A. Miller, CFA, President and Chief Executive Officer, stated, “We were pleased with the amount of leasing that we completed during the quarter, and over the year as a whole, to high-quality tenants. While we remain focused on our core operations through cost control and actively addressing known forthcoming lease expirations, we have not lost sight of our strategic objectives. We are encouraged by increased activity in the market, both from a leasing and capital transactions perspective, and remain committed to selectively growing our portfolio through thoughtful acquisitions.”

Results for the Fourth Quarter Ended December 31, 2010

All prior period per share amounts have been retroactively restated to reflect the stockholder-approved recapitalization of our common stock. Current period per share amounts reflect the issuance of 13.8 million shares of common stock. Both the recapitalization and issuance of stock

occurred during the first quarter of 2010.

Piedmont’s net income available to common stockholders was $28.7 million, or $0.17 per diluted share, for the fourth quarter of 2010, compared with net income of $25.9 million, or $0.16 per diluted share, for the fourth quarter of 2009. FFO totaled $67.9 million, or $0.39 per diluted share, for the fourth quarter of 2010 as compared to FFO of $69.5 million, or $0.44 per diluted share, for the fourth quarter of 2009. The fourth quarter of 2010 FFO results reflected approximately $0.04 in dilution per share related to the issuance of 13.8 million shares of common stock during first quarter of 2010. Adjusted FFO (“AFFO”) for the fourth quarter of 2010 totaled $38.1 million, or $0.22 per diluted share, as compared to $47.4 million, or $0.30 per diluted share, in the fourth quarter of 2009, with the decline due primarily to increased capital expenditures related to new leasing activity.

Revenues for the quarter ended December 31, 2010 totaled $151.3 million, compared to $149.4 million in the same period in 2009. Property operating expenses were $60.4 million in the fourth quarter of 2010 compared to $57.3 million in the fourth quarter of 2009. Same store net operating income for the quarter was $83.0 million, 2.7% lower than the $85.3 million for the fourth quarter of 2009, reflecting primarily the impact of rental rate roll downs on some recent new leases.

Results for the Year Ended December 31, 2010

Piedmont’s net income available to common stockholders was $120.4 million, or $0.70 per diluted share, for the twelve months ended December 31, 2010, compared with net income of $74.7 million, or $0.47 per diluted share, for the comparable 2009 period. Net income exclusive of impairment charges was $130.0 million in 2010 compared to $112.3 million in 2009. FFO for the year ended December 31, 2010, totaled $271.6 million, or $1.59 per diluted share, as compared to FFO of $239.3 million, or $1.51 per diluted share, for the year ended December 31, 2009. The 2010 FFO results reflected approximately $0.12 in dilution per share related to the issuance of 13.8 million shares of common stock during first quarter of 2010. Core FFO, which excludes impairment charges, was $281.3 million, or $1.65 per diluted share, for 2010, compared to $ 276.9 million, or $1.75 per diluted share, for 2009. The 2010 Core FFO results reflected approximately $0.12 in dilution per share related to the previously mentioned issuance of 13.8 million shares of common stock during first quarter of 2010. Adjusted FFO (“AFFO”) for the year ended December 31, 2010, totaled $215.7 million, or $1.26 per diluted share, as compared to $228.4 million, or $1.44 per diluted share, for the same period in 2009.

Revenues for the year ended December 31, 2010, totaled $588.8 million compared to $598.5 million in the same period in 2009. Property operating expenses were $217.9 million in 2010 compared to $230.6 million in 2009. Same store net operating income for the year was $347.6 million, 1.4% lower than the $352.6 million in 2009.

Leasing Update

During the fourth quarter of 2010, the Company executed leases for 783,000 square feet, all of which were office leases, spread throughout its markets. Of the leases signed in the quarter, 389,000 square feet, or 50 percent, was renewal-related and 394,000 square feet was new or expansion-related with existing tenants. As of December 31, 2010, the Company’s office portfolio was 89.2 percent leased with a weighted average lease term remaining of 5.8 years. The Company’s leased percentage increased 20 basis points from the end of the third quarter, but decreased 90 basis points year over year. That year over year decrease was primarily related to the acquisition of a vacant 142,000 square foot building in the Atlanta market at the end of the third quarter. Excluding the newly-acquired building in Atlanta from consideration, the portfolio was 89.9 percent leased as of December 31, 2010. The Company is actively managing its upcoming lease expirations, including several large 2011 and 2012 lease expirations.

A detailed presentation of the Company’s leasing activity can be found on pages 6 and 21 of its quarterly supplemental reporting package. Additional information on the quarterly supplemental reporting package can be found below.

Dividend

During the quarter ended December 31, 2010, the Company paid a quarterly dividend in the amount of $0.315 per share for all classes of common stock, bringing total dividends paid for the year ended December 31, 2010, to $1.26 per share.

Balance Sheet and Capital Markets Activities

As of December 31, 2010, Piedmont’s total gross assets were $5.3 billion with total debt of $1.4 billion. The Company’s total debt-to-gross assets ratio at the end of the fourth quarter of 2010 was 26.6 percent and the quarter’s net debt (total debt less cash and cash equivalents) to annualized core EBITDA ratio was 3.9 times. The Company’s fixed charge coverage ratio was 4.9 times. As of December 31, 2010, Piedmont had cash and capacity on its unsecured credit line of approximately $540 million. The Company has a $250 million unsecured term loan maturing in 2011.

On November 7, 2010, all of Piedmont’s 39.7 million shares of Class B-2 common stock converted on a one-for-one basis into the Company’s Class A common stock. On January 30, 2011, the final tranche of Piedmont’s Class B common stock converted on a one-for-one basis into the Company’s Class A common stock; therefore, all of the Company’s outstanding shares of common stock are now Class A common shares and traded on the New York Stock Exchange.

Acquisitions and Dispositions

As previously communicated, the Company purchased, for $65.6 million, two Class A, eight-story office buildings (the “Meridian Crossings Buildings”) containing approximately 384,000 combined rentable square feet and located in the Minneapolis, MN market. The Meridian Crossings Buildings, which were constructed in 1997 and 1998, are primarily leased through 2023 to U.S.

Bank, an existing tenant within the Piedmont portfolio. The two buildings combined are approximately 96 percent leased.

During the fourth quarter of 2010, Piedmont completed two dispositions: the sale of 111 Sylvan Avenue in Englewood Cliffs, NJ for $55 million; and the sale of a joint venture property, of which Piedmont’s proportionate share was approximately 4 percent, for $5.3 million.

Guidance for 2011

The Company introduced its financial guidance for full-year 2011 based upon management’s expectations as follows:

These estimates reflect management’s view of current market conditions and incorporate certain economic and operational assumptions and projections. These estimates exclude any significant acquisitions or dispositions which would result in a change in the Company’s 2011 outlook and guidance. Actual results could differ from these estimates. Note that individual quarters may fluctuate on both a cash basis and an accrual basis due to timing of repairs and maintenance, capital expenditures, capital markets activities and one-time revenue or expense events. In addition, the Company’s guidance is based on information available to management as of the date of this release.

Non-GAAP Financial Measures

This release contains certain supplemental non-GAAP financial measures such as FFO, AFFO, Core FFO, Same store net operating income, Net income exclusive of impairment charges, and Core EBITDA. See below for definitions and reconciliations of these metrics to their most comparable GAAP metric.

Conference Call Information

Piedmont has scheduled a conference call and an audio webcast for Friday, February 11, 2011 at 10:00 A.M. Eastern Time. Dial-in numbers are (877) 407-9039 for participants in the United States and (201) 689-8470 for international participants. The conference identification number is 365345. The live audio webcast of the call may be accessed on the Company’s website at www.piedmontreit.com in the Investor Relations section. A replay of the conference call will be available until February 25, 2010, and can be accessed by dialing (877) 870-5176, or (858) 384-

5517 for international participants, followed by passcode 365345. A webcast replay will also be available after the conference call in the Investor Relations section of the Company’s website. During the audio webcast and conference call, the Company’s management team will review fourth quarter 2010 performance, discuss recent events, and conduct a question-and-answer period.

Supplemental Information

Quarterly Supplemental Information as of and for the three and twelve months ended December 31, 2010, can be accessed on the Company’s website under the Investor Relations section at www.piedmontreit.com.

About Piedmont Office Realty Trust

Piedmont Office Realty Trust, Inc. is a fully-integrated and self-managed real estate investment trust (“REIT”) specializing in the acquisition, ownership, management, development and disposition of primarily high-quality Class A office buildings located predominantly in large U.S. office markets and leased principally to high-credit-quality tenants. Since its first acquisition in 1998, the Company has acquired $5.5 billion of office and industrial properties. Rated as an investment-grade company by Standard & Poor’s and Moody’s, Piedmont has maintained a low-leverage strategy while acquiring its properties.

Forward Looking Statements

Certain statements contained in this press release constitute forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”) and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). We intend for all such forward-looking statements to be covered by the safe-harbor provisions for forward-looking statements contained in Section 27A of the Securities Act and Section 21E of the Exchange Act, as applicable. Such information is subject to certain risks and uncertainties, as well as known and unknown risks, which could cause actual results to differ materially from those projected or anticipated. Therefore, such statements are not intended to be a guarantee of our performance in future periods. Such forward-looking statements can generally be identified by our use of forward-looking terminology such as “may,” “will,” “expect,” “intend,” “anticipate,” “believe,” “continue” or similar words or phrases that are predictions of future events or trends and which do not relate solely to historical matters. Examples of such statements in this press release include the quality of the Company’s assets; the Company’s leasing and transactional activity prospects; and the Company’s estimated range of Net Income, Depreciation and Amortization, Core FFO and Core FFO per diluted share for the year ending December 31, 2011.

The following are some of the factors that could cause our actual results and expectations to differ materially from those described in our forward-looking statements: our ability to successfully identify and consummate suitable acquisitions; current adverse market and economic conditions; lease terminations or lease defaults, particularly by one of our large lead

tenants; the impact of competition on our efforts to renew existing leases or re-let space; changes in the economies and other conditions of the office market in general and of the specific markets in which we operate; economic and regulatory changes; additional risks and costs associated with directly managing properties occupied by government tenants; adverse market and economic conditions and related impairments to our assets, including, but not limited to, receivables, real estate assets and other intangible assets; the success of our real estate strategies and investment objectives; availability of financing; costs of complying with governmental laws and regulations; uncertainties associated with environmental and other regulatory matters; our ability to continue to qualify as a REIT under the Internal Revenue Code; the impact of outstanding or potential litigation; and other factors detailed in our most recent Annual Report on Form 10-K and our Quarterly Report on Form 10-Q as of and for the period ended September 30, 2010, and other documents we file with the Securities and Exchange Commission.

Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. We cannot guarantee the accuracy of any such forward-looking statements contained in this press release, and we do not intend to publicly update or revise any forward-looking statements, whether as a result of new information, future events, or otherwise.

Research Analysts Contact:

Eddie Guilbert

770-418-8592

research.analysts@piedmontreit.com

or

ICR Inc.

Evelyn Infurna

203-682-8346

Evelyn.infurna@icrinc.com

All Other Shareholder Inquiries, Contact:

Shareholder Relations

866-354-3485

investor.services@piedmontreit.com

Piedmont Office Realty Trust, Inc.

Consolidated Balance Sheets

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Piedmont Office Realty Trust, Inc.

Consolidated Statements of Income

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Piedmont Office Realty Trust, Inc.

Funds From Operations, Core Funds From Operations and Adjusted Funds From Operations

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*Definitions

Funds From Operations (“FFO”): FFO is calculated in accordance with the current National Association of Real Estate Investment Trusts (“NAREIT”) definition. NAREIT currently defines FFO as net income (computed in accordance with GAAP), excluding gains or losses from sales of property, adding back depreciation and amortization on real estate assets, and after the same adjustments for unconsolidated partnerships and joint ventures. Such factors can vary among owners of identical assets in similar conditions based on historical cost accounting and useful-life estimates. FFO may provide valuable comparisons of operating performance between periods and with other REITs. FFO is a non-GAAP financial measure and should not be viewed as an alternative measurement of our operating performance to net income. We believe that FFO is a beneficial indicator of the performance of an equity REIT. However, other REITs may not define FFO in accordance with the NAREIT definition, or may interpret the current NAREIT definition differently than we do; therefore, our computation of FFO may not be comparable to that of such other REITs.

Core Funds From Operations (“Core FFO”): We calculate Core FFO by starting with FFO, as defined by NAREIT, and adjust for certain non-recurring items such as impairment losses and other extraordinary items. Such items create significant earnings volatility. We believe Core FFO provides a meaningful measure of our operating performance and more predictability regarding future earnings potential. Core FFO is a non-GAAP financial measure and should not be viewed as an alternative measurement of our operating performance to net income; therefore, it should not be compared to other REITs’ equivalent to Core FFO.

Adjusted Funds From Operations (“AFFO”): AFFO is calculated by deducting from Core FFO non-incremental capital expenditures and adding back non-cash items including non-real estate depreciation, straight lined rents and fair value lease revenue, non-cash components of interest expense and compensation expense, and by making similar adjustments for unconsolidated partnerships and joint ventures. Although AFFO may not be comparable to that of other REITs, we believe it provides a meaningful indicator of our ability to fund cash needs and to make cash distributions to equity owners. AFFO is a non-GAAP financial measure and should not be viewed as an alternative measurement of our operating performance to net income, as an alternative to net cash flows from operating activities or as a measure of our liquidity.

Piedmont Office Realty Trust, Inc.

Same Store Net Operating Income

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*Definitions

Core EBITDA: Defined as net income before interest, taxes, depreciation and amortization and incrementally removing any impairment losses, gains or losses from sales of property, or other extraordinary items. We do not include impairment losses in this measure because we feel these types of losses create volatility in our earnings and make it difficult to determine the earnings generated by our ongoing business. We believe Core EBITDA is a reasonable measure of our liquidity. Core EBITDA is a non-GAAP financial measure and should not be viewed as an alternative measurement of cash flows from operating activities or other GAAP basis liquidity measures. Other REITs may calculate Core EBITDA differently and our calculation should not be compared to that of other REITs.

Core net operating income (“Core NOI”): Core NOI is defined as real estate operating income with the add-back of corporate general and administrative expense, depreciation and amortization, and casualty and impairment losses and the deduction of income and expense associated with lease terminations and income associated with property management performed by Piedmont for other organizations. We present this measure on a cash basis, which eliminates the effects of straight lined rents and fair value lease revenue. The company uses this measure to assess its operating results and believes it is important in assessing operating performance. Core NOI is a non-GAAP measure which does not have any standard meaning prescribed by GAAP and therefore may not be comparable to similar measures presented by other companies.

Same store net operating income (“Same Store NOI”): Same Store NOI is calculated as the Core NOI attributable to the properties owned or placed in service during the entire span of the current and prior year reporting periods. Same Store NOI excludes amounts attributable to industrial properties. We present this measure on a cash basis, which eliminates the effects of straight lined rents and fair value lease revenue. We believe Same Store NOI is an important measure of comparison of our stabilized properties’ operating performance. Other REITs may calculate Same Store NOI differently and our calculation should not be compared to that of other REITs.