UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT
PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Date of report (Date of earliest event reported): March 25, 2013

SELECT INCOME REIT
(Exact Name of Registrant as Specified in Its Charter)

617-796-8303
(Registrant's Telephone Number, Including Area Code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 9.01.    Financial Statements and Exhibits.

              This Current Report on Form 8-K includes (i) the Statement of Revenues and Certain Operating Expenses of three properties located at 45101 - 45301 Warp Drive, Sterling, Virginia, or, collectively, Warp Drive, for the year ended December 31, 2011 (audited) and the nine months ended September 30, 2012, pursuant to the requirements of Rule 3-14 of Regulation S-X and (ii) unaudited pro forma financial data for Select Income REIT, or the Company, which gives effect to transactions the Company has completed since January 1, 2012, as if those transactions all occurred on that date.

              This historical and pro forma financial information is not necessarily indicative of the expected financial position or results of operations of the Company for any future period. Differences could result from many factors, including future changes in the Company's investments, changes in interest rates and changes in the capital structure of the Company.

              Neither the Company nor its affiliates are related to the sellers of Warp Drive. The historical financial statements listed in Item 9.01(a) present the results of operations of Warp Drive during periods prior to their acquisition by the Company and exclude, as permitted by Rule 3-14 of Regulation S-X, items of revenue and expense which the Company expects may not be comparable to the expected future operation by the Company. In assessing Warp Drive, the Company considered each property's revenue sources, including those which have been affected, and are expected to be affected in the future, by factors including, but not limited to, demand, supply and competitive factors present in the local and national markets for single tenant, net leased properties and the ability of tenants to make payments when due. The Company also considered the properties' expenses including, but not limited to, utility costs, tax rates and other expenses, and the portion of such expenses which may be recovered from tenants. Changes in these factors or other factors described in the notes to the pro forma data provided below will cause future operating results to differ from the historical and pro forma operating results presented, but cannot be predicted at this time; however, after reasonable inquiry, the Company is not currently aware of any other material factors relating to the properties that would cause the financial information reported herein not to be indicative of future operating results.

(a)

Financial Statements of Real Estate Operations Acquired.

Statement of Revenues and Certain Operating Expenses of Warp Drive

(b)

Pro Forma Financial Information.

i

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Board of Trustees of Select Income REIT:

              We have audited the accompanying statement of revenues and certain operating expenses of 45101 - 45301 Warp Drive for the year ended December 31, 2011. This financial statement is the responsibility of Select Income REIT's management. Our responsibility is to express an opinion on the financial statement based on our audit.

              We conducted our audit in accordance with auditing standards generally accepted in the United States. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statement is free of material misstatements. We were not engaged to perform an audit of 45101 - 45301 Warp Drive's internal control over financial reporting. Accordingly, we express no such opinion. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statement, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audit provides a reasonable basis for our opinion.

              The accompanying financial statement was prepared for the purpose of complying with the rules and regulations of the Securities and Exchange Commission for inclusion in Amendment No. 1 to the Registration Statement on Form S-11 of Select Income REIT, as described in Note 1, and is not intended to be a complete presentation of 45101 - 45301 Warp Drive's revenues and expenses.

              In our opinion, the financial statement referred to above presents fairly, in all material respects, the revenues and certain operating expenses described in Note 1 of 45101 - 45301 Warp Drive for the year ended December 31, 2011, in conformity with U.S. generally accepted accounting principles.

/s/ ERNST & YOUNG LLP

Boston, Massachusetts
November 23, 2012, except for Note 3,
      as to which the date is November 30, 2012

F-1

45101 - 45301 Warp Drive

Statement of Revenues and Certain Operating Expenses

See accompanying notes.

F-2

45101 - 45301 Warp Drive
Notes to Statement of Revenues and Certain Operating Expenses
Nine months ended September 30, 2012 (unaudited) and year ended December 31, 2011

1. General Information and Summary of Significant Accounting Policies

              TMW Weltfonds Loudoun, L.P., a Delaware limited partnership, owns and operates three properties located at 45101 - 45301 Warp Drive, in Sterling, Virginia (the "Properties"). Select Income REIT ("SIR") has signed a Purchase and Sale Agreement as of October 19, 2012 with TMW Weltfonds Loudoun, L.P. to acquire 45101 - 45301 Warp Drive and will assume management and ownership responsibilities upon closing.

              The accompanying financial statement has been prepared in accordance with Rule 3-14 of Regulation S-X of the Securities and Exchange Commission for inclusion in the Registration Statement on Form S-11 of SIR. Accordingly, certain historical expenses that may not be comparable to the expenses expected to be incurred in the future have been excluded. Excluded expenses consist of depreciation and amortization, interest expense and other costs not directly related to the future operations of the Properties.

              Use of Estimates.    Preparation of this financial statement in conformity with U.S. generally accepted accounting principles requires SIR's management to make estimates and assumptions that may affect the amounts reported in the financial statement and related notes. Actual results could differ from those estimates.

              Revenue Recognition.    The tenant lease is accounted for as an operating lease. Rental income is recognized on a straight line basis over the term of the lease agreement. Straight line rent adjustments included in rental income on the statement of revenues and certain operating expenses totaled $934,393 for the year ended December 31, 2011, and $1,077,815 included in the unaudited period for the nine months ended September 30, 2012.

              Reimbursement from Tenants.    The tenant bears 100% of the cost for operating and real estate tax expense of the buildings.

              Repairs and Maintenance.    Expenditures for repairs and maintenance are expensed as incurred.

2. Leases

              TMW Weltfonds Loudoun, L.P., as lessor, has entered into three non-cancelable operating leases at the Properties. These leases will be assumed by SIR assuming the purchase is completed in November 2012. Future minimum rentals under the lease in effect at December 31, 2011, are summarized as follows:

F-3

45101 - 45301 Warp Drive
Notes to Statement of Revenues and Certain Operating Expenses
Nine months ended September 30, 2012 (unaudited) and year ended December 31, 2011

(Continued)

2. Leases (Continued)

              The leases are for twelve years and provide for 100% recovery of operating and real estate tax expense and include two (2) successive five (5)-year renewal options, commencing immediately following the end of the Lease Term.

3. Subsequent Events

              SIR acquired the Properties from TMW Weltfonds Loudoun, L.P. on November 29, 2012 and will assume management and ownership responsibilities.

F-4

SELECT INCOME REIT

Introduction to Unaudited Pro Forma Consolidated Financial Statements

(dollars in thousands)

              Select Income REIT, or we or us, was formerly a wholly owned subsidiary of CommonWealth REIT, or CWH, a NYSE-listed real estate investment trust, or REIT, that primarily owns office properties. CWH created us to concentrate its ownership of certain net leased lands located in Hawaii that CWH purchased in 2003 and 2005 from the Damon Estate and the Campbell Estate, respectively, and other net leased properties. On February 16, 2012, CWH contributed 251 properties with a combined total of approximately 21.4 million rentable square feet, or the Initial Properties, to us and in return we issued to CWH: (1) 22,000,000 of our common shares of beneficial interest, $.01 par value per share, or Shares (including 1,000 Shares initially issued to CWH on December 21, 2011 in connection with our formation); and (2) a $400,000 demand promissory note, or the CWH Note.

              On March 6, 2012, we priced our initial public offering, or the IPO, of 8,000,000 Shares. The sale of those Shares and an additional 1,200,000 Shares pursuant to the full exercise of the underwriters' option to purchase additional Shares, closed on March 12, 2012, and we became a public company. Simultaneous with the closing of the IPO, we entered into a $500,000 revolving credit facility that is available for general business purposes, including acquisitions. We used the net proceeds from the IPO and borrowings under our revolving credit facility to repay in full the CWH Note and to reimburse CWH for costs that CWH incurred in connection with our organization and preparation for the IPO.

              Since the IPO, we have acquired 21 properties from unrelated third parties with a combined total of approximately 4.0 million rentable square feet for an aggregate purchase price of $596,333, including the assumption of $26,000 in mortgage debt and excluding closing costs. Details of these acquisitions are as follows:

•

In June 2012, we acquired a single tenant, net leased office property located in Provo, UT with approximately 0.4 million rentable square feet. The purchase price was $85,500, excluding closing costs.



•

In June 2012, we acquired a single tenant, net leased office property located in Englewood, CO with approximately 0.1 million rentable square feet. The purchase price was $18,900, excluding closing costs.



•

In July 2012, we acquired two single tenant, net leased office properties located in Windsor, CT with a combined total of approximately 0.3 million rentable square feet. The aggregate purchase price was $27,175, excluding closing costs.



•

In July 2012, we acquired a single tenant, net leased office property located in Topeka, KS with approximately 0.1 million rentable square feet. The purchase price was $19,400, excluding closing costs.



•

In August 2012, we acquired a single tenant, net leased industrial property located in Huntsville, AL with approximately 1.4 million rentable square feet. The purchase price was $72,782, excluding closing costs.



•

In September 2012, we acquired two single tenant, net leased office properties located in Carlsbad, CA with a combined total of approximately 0.1 million rentable square feet. The aggregate purchase price was $24,700, including the assumption of $18,500 of mortgage debt and excluding closing costs.

F-5

SELECT INCOME REIT

Introduction to Unaudited Pro Forma Consolidated Financial Statements (Continued)

(dollars in thousands)

•

Also in September 2012, we acquired a single tenant, net leased office property located in Chelmsford, MA with approximately 0.1 million rentable square feet. The purchase price was $12,200, including the assumption of $7,500 of mortgage debt and excluding closing costs.



•

In November 2012, we acquired a single tenant, net leased office property located in Sunnyvale, CA with approximately 0.1 million rentable square feet. The purchase price was $28,050, excluding closing costs.



•

Also in November 2012, we acquired a leasable land parcel located on the island of Oahu, HI with less than 0.1 million square feet. The purchase price was $6,300, excluding closing costs.



•

Also in November 2012, we acquired three single tenant, net leased office properties located in Sterling, VA with a combined total of approximately 0.3 million rentable square feet. The aggregate purchase price was $85,600, excluding closing costs.



•

In December 2012, we acquired a single tenant, net leased office property located in Columbia, MD with approximately 0.1 million rentable square feet. The purchase price was $40,500, excluding closing costs.



•

Also in December 2012, we acquired a single tenant, net leased office property located in Ann Arbor, MI with approximately 0.1 million rentable square feet. The purchase price was $16,906, excluding closing costs.



•

In January 2013, we acquired two single tenant, net leased office properties located in Addison, TX with a combined total of approximately 0.6 million rentable square feet. The aggregate purchase price was $105,000, excluding closing costs.



•

In February 2013, we acquired two single tenant, net leased office properties located in Provo, UT with a combined total of approximately 0.1 million rentable square feet. The aggregate purchase price was $34,720, excluding closing costs.



•

In March 2013, we acquired a single tenant, net leased office property located in San Antonio, TX with approximately 0.1 million rentable square feet. The purchase price was $18,600, excluding closing costs.

              On December 11, 2012, we completed the sale of 8,050,000 Shares, including 1,050,000 Shares sold when the underwriters exercised in full their option to purchase additional shares, in a public offering at a price of $24.00 per share, raising net proceeds of approximately $182,843, after deducting the underwriting discounts and commissions and other offering expenses. We used the net proceeds to partially repay amounts outstanding under our revolving credit facility and for general business activities, including acquisitions.

              The following unaudited pro forma consolidated balance sheet as of December 31, 2012 is intended to present the financial position of us and our consolidated subsidiaries as if the transactions described in the notes had been consummated as of December 31, 2012. The following unaudited pro forma consolidated statements of income and comprehensive income for the year ended December 31, 2012 are intended to present our results of operations as if the transactions described in the notes had been consummated on January 1, 2012.

F-6

SELECT INCOME REIT

Introduction to Unaudited Pro Forma Consolidated Financial Statements (Continued)

(dollars in thousands)

              The following unaudited pro forma consolidated financial statements are not necessarily indicative of the expected financial position or results of our operations for any future period. Differences could result from many factors, including future changes in our investments, changes in interest rates and changes in our capital structure. The pro forma information should be read in conjunction with the financial statements and related notes, "Management's Discussion and Analysis of Financial Condition and Results of Operations" and "Risk Factors" included in our Annual Report on Form 10-K for the year ended December 31, 2012.

F-7

SELECT INCOME REIT

Unaudited Pro Forma Consolidated Balance Sheet

December 31, 2012

(amounts in thousands, except share data)

See accompanying notes

F-8

SELECT INCOME REIT

Unaudited Pro Forma Consolidated Statements of Income and Comprehensive Income
For the Year Ended December 31, 2012
(amounts in thousands, except per share data)

See accompanying notes

F-9

SELECT INCOME REIT

Notes to Unaudited Pro Forma Consolidated Financial Statements

(dollars in thousands, except Share data)

Basis of Presentation

(A)

We are a Maryland real estate investment trust that was organized on December 19, 2011 as a wholly owned subsidiary of CWH. On February 16, 2012, CWH contributed 251 properties with a total of approximately 21.4 million rentable square feet, or the Initial Properties. In return, we issued to CWH: (i) 22,000,000 Shares (including 1,000 Shares initially issued to CWH on December 21, 2011 in connection with our formation); and (ii) a $400,000 demand promissory note, or the CWH Note.

On March 6, 2012, we priced our initial public offering, or IPO, of 8,000,000 Shares. The sale of these shares and an additional 1,200,000 of our Shares pursuant to the exercise in full of our IPO underwriters' option to purchase additional Shares closed on March 12, 2012, or the Closing Date, and we became a public company. We used the net proceeds from the IPO and borrowings under our revolving credit facility to repay in full the CWH Note.

Unaudited Pro Forma Consolidated Balance Sheet Adjustments

(B)

Represents the effect of the acquisition of five properties since December 31, 2012. As of December 31, 2012, we had funded deposits of $10,000 related to these acquisitions which were applied to purchase prices for pro forma purposes, and we assumed acquisitions were otherwise funded primarily with draws on our revolving credit facility. Purchase price allocations are estimated for pro forma purposes and actual allocations may differ. Estimated pro forma purchase price allocations are as follows:

F-10

SELECT INCOME REIT

Notes to Unaudited Pro Forma Consolidated Financial Statements (Continued)

(dollars in thousands, except Share data)

Unaudited Pro Forma Consolidated Statements of Income and Comprehensive Income Adjustments

(C)

Represents the net effect of our formation and IPO. We issued a total of 31,200,000 common shares as described in Note (A) above and incurred interest expense related to borrowings under our revolving credit facility. Interest expense is calculated as follows:

(D)

Represents the net effect on interest expense related to our $350,000 term loan which closed on July 12, 2012 and the application of the net proceeds to primarily repay amounts outstanding on our revolving credit facility. Interest expense includes term loan interest and $2,242 of deferred financing costs amortized over the five year term, less interest expense savings from interest forgone under our revolving credit facility (excluding revolving credit facility fees and deferred financing cost amortization). Term loan interest expense is based on the one month LIBOR rate, plus 1.55%. The premium of 1.55% is specified in our term loan for leverage ratios of less than or equal to 35%. An increase in the interest rate by 100 bps would increase our annual term loan interest expense by approximately $3,500.

F-11

SELECT INCOME REIT

Notes to Unaudited Pro Forma Consolidated Financial Statements (Continued)

(dollars in thousands, except Share data)

Pro Forma Interest Expense Calculation

(E)

Represents the effect of our public offering of 8,050,000 Shares, including 1,050,000 Shares sold when the underwriters exercised in full their option to purchase additional shares, which closed on December 11, 2012. Interest savings is calculated assuming net proceeds from the offering of approximately $182,843 were used to primarily repay amounts outstanding under our revolving credit facility using the weighted average interest rate for the period from March 12, 2012 to December 31, 2012 of 1.54%.

(F)

Represents the revenues and operating expenses of properties we acquired from the Closing Date to December 31, 2012 for an aggregate purchase price of $438,013, including the assumption of $26,000 of mortgage debt and excluding acquisition costs. Operating adjustments are based on historical results, except that, for pro forma purposes, we have assumed that the lease that is in place at the Sunnyvale, CA property and the leases with the prior owners that were signed immediately following the acquisition of the Provo, UT and Huntsville, AL properties were in place as of January 1, 2012. Interest expense includes interest payments due under the existing debt assumed ($7,500 of debt at an interest rate of 5.689% and $18,500 of debt at an interest rate of 5.95%).

(G)

Represents the revenues and operating expenses for the period indicated of the properties described in Note (B) above. Operating adjustments are based on historical results, except that, for pro forma purposes, we have assumed that the lease with the prior owner that was signed immediately following the acquisition of the Addison, TX property was in place as of January 1, 2012.

F-12

SELECT INCOME REIT

Notes to Unaudited Pro Forma Consolidated Financial Statements (Continued)

(dollars in thousands, except Share data)

(H)

Represents the effect on rental income of the non-cash amortization of above and below market leases for the properties described in Notes (F) and (G). We amortize capitalized above and below market lease values as a reduction or an increase, respectively, to rental income over the remaining terms of the leases.

(I)

Represents the effect on depreciation and amortization expense for the properties described in Notes (F) and (G). Depreciation expense is computed using a 40 year life for building and improvements and a 12 year life for personal property. The adjustment to depreciation and amortization expense for the year ended December 31, 2012 related to properties acquired from the Closing Date to December 31, 2012 represents pro forma depreciation and amortization expense from January 1, 2012 through the respective date of acquisition.

(J)

Adjusts for non recurring acquisition related costs of $2,470 for year ended December 31, 2012.

(K)

Represents the effect on general and administrative expenses for the properties described in Notes (F) and (G). General and administrative expenses are based on our contractual obligation under our business management agreement with Reit Management & Research LLC. The adjustment to general and administrative expense for the year ended December 31, 2012 related to properties acquired from the Closing Date to December 31, 2012 represents pro forma general and administrative expense from January 1, 2012 through the respective date of acquisition.

(L)

Adjusts interest expense for the properties described in Notes (F) and (G). The adjustment to interest expense for the year ended December 31, 2012 related to properties acquired from the Closing Date to December 31, 2012 represents pro forma interest expense from January 1, 2012 through the respective date of acquisition. The pro forma interest expense adjustment is calculated using the weighted average interest rate for our revolving credit facility for the period from March 12, 2012 to December 31, 2012 of 1.54%. An increase in our variable interest rate by 100 bps would increase our annual pro forma acquisitions related interest expense by approximately $5,690.

F-13

SIGNATURES

              Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: March 25, 2013

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Item 9.01. Financial Statements and Exhibits.