N-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form N-Q

QUARTERLY SCHEDULE OF PORTFOLIO HOLDINGS OF REGISTERED
MANAGEMENT INVESTMENT COMPANIES

811-22351

Investment Company Act File Number

Build America Bond Portfolio

(Exact Name of Registrant as Specified in Charter)

Two International Place, Boston, Massachusetts 02110

(Address of Principal Executive Offices)

Maureen A. Gemma

Two International Place, Boston, Massachusetts 02110

(Name and Address of Agent for Services)

(617) 482-8260

(Registrant’s Telephone Number, Including Area Code)

October 31

Date of Fiscal Year End

January 31, 2011

Date of Reporting Period

Item 1. Schedule of Investments

Build America Bond Portfolio as of January 31, 2011

PORTFOLIO OF INVESTMENTS (Unaudited)

Taxable Municipal Securities — 98.1%⁽¹⁾

Principal
Amount
(000’s omitted)		Security	Value
Education — 4.7%
$	1,875	University of Texas, 6.276%, 8/15/41	$	1,924,238
	260	University of Virginia, 6.20%, 9/1/39		285,659
			$	2,209,897
General Obligations — 24.7%
$	140	California, 7.55%, 4/1/39	$	145,165
	1,000	California, 7.70%, 11/1/30		1,027,390
	125	California, 7.95%, 3/1/36		128,562
	1,500	Commonwealth of Pennsylvania, 5.85%, 7/15/30		1,479,570
	740	Connecticut, 5.632%, 12/1/29		738,401
	1,000	Denton County, TX, 5.968%, 7/15/35		1,001,680
	75	Denver, CO, City & County School District No. 1, 5.664%, 12/1/33		74,936
	1,000	Detroit, MI, City School District, 7.747%, 5/1/39		1,049,270
	225	Kauai, HI, 5.763%, 8/1/33		223,153
	1,000	Metropolitan Government of Nashville and Davidson County, TN, 5.707%, 7/1/34		974,380
	1,030	Montgomery County, PA, 6.03%, 9/1/39		1,047,211
	1,500	New York, NY, 6.646%, 12/1/31		1,546,320
	200	Oxford, MI, 6.50%, 5/1/39		192,000
	1,000	Santa Monica, CA, Community College District, 6.763%, 8/1/34		1,006,470
	400	Southwest Regional Sanitary Sewer & Water Authority, MI, 6.50%, 4/1/40		392,268
	175	Texas, 5.517%, 4/1/39		172,209
	275	Washington, 5.481%, 8/1/39		273,859
			$	11,472,844
Hospital — 1.6%
$	250	King County, WA, Public Hospital District No. 1, 7.90%, 6/15/30	$	250,915
	500	King County, WA, Public Hospital District No. 1, 8.00%, 6/15/40		506,820
			$	757,735
Lease Revenue/Certificates of Participation — 4.4%
$	1,525	New Jersey Transportation Trust Fund Authority, 6.561%, 12/15/40	$	1,539,060
	500	Oregon Department of Administrative Services, 6.18%, 5/1/35		490,100
			$	2,029,160
Other Revenue — 1.1%
$	250	Battery Park City Authority, NY, 6.375%, 11/1/39	$	248,500
	250	Florida State Board of Education, 6.584%, 7/1/29		251,488
			$	499,988
Public Power/Electric Utilities — 14.8%
$	1,000	American Municipal Power-Ohio, Inc., 7.499%, 2/15/50	$	1,026,870
	1,000	Indiana Municipal Power Agency, 5.594%, 1/1/42		895,890
	1,000	Municipal Electric Authority of Georgia, 6.655%, 4/1/57		964,710
	1,000	Nebraska Public Power District, 5.323%, 1/1/30		908,540
	1,000	Northern Illinois Municipal Power Agency, 7.62%, 1/1/30		1,077,000
	500	Orlando, FL, Utilities Commission, 5.662%, 10/1/40		486,790
	1,500	San Antonio, TX, Electric & Gas Revenue, 6.168%, 2/1/41		1,511,115
			$	6,870,915
Special Tax Revenue — 11.3%
$	980	Massachusetts School Building Authority, 5.715%, 8/15/39	$	986,174
	1,000	Miami-Dade County, FL, Transit Sales Surtax Revenue, 5.534%, 7/1/32		936,180
	1,115	Miami-Dade County, FL, Transit Sales Surtax Revenue, 5.624%, 7/1/40		1,003,366

1

Principal
Amount
(000’s omitted)		Security	Value
$	1,000	New York City Transitional Finance Authority, 5.508%, 8/1/37	$	963,340
	1,385	New York Urban Development Corp., 5.77%, 3/15/39		1,365,929
			$	5,254,989
Transportation — 8.8%
$	450	Maryland Transportation Authority, 5.604%, 7/1/30	$	442,557
	500	Maryland Transportation Authority, 5.888%, 7/1/43		504,905
	1,000	New Jersey Turnpike Authority, 7.102%, 1/1/41		1,061,000
	1,500	Pennsylvania Turnpike Commission, 5.511%, 12/1/45		1,313,220
	790	Pennsylvania Turnpike Commission, 6.378%, 12/1/37		752,767
			$	4,074,449
Water and Sewer — 26.7%
$	750	Chesapeake, VA, Water and Sewer Revenue, 6.283%, 7/1/40	$	777,608
	1,460	Chicago, IL, Metropolitan Water Reclamation District, 5.72%, 12/1/38		1,425,515
	1,500	East Bay, CA, Municipal Utility District Water System Revenue, 5.874%, 6/1/40		1,488,240
	100	Jea, FL, Water and Sewer Revenue, 6.21%, 10/1/33		102,074
	380	Knoxville, TN, Wastewater System Revenue, 6.50%, 4/1/43		388,105
	1,000	Los Angeles, CA, Department of Water and Power Waterworks Revenue, 6.008%, 7/1/39		984,540
	1,325	Metropolitan St. Louis, MO, Sewer District Wastewater System Revenue, 5.856%, 5/1/39		1,317,434
	1,500	Metropolitan Water District of Southern California, 6.538%, 7/1/39		1,502,580
	1,525	New York, NY, Municipal Water Finance Authority, 6.452%, 6/15/41		1,537,856
	1,000	San Diego County, CA, Water Authority, 6.138%, 5/1/49		1,013,840
	1,000	Washington County, OR, Clean Water Services, 5.701%, 10/1/30		991,390
	1,000	Williamsport Sanitary Authority, PA, 5.75%, 1/1/40		887,340
			$	12,416,522
Total Taxable Municipal Securities — 98.1% (identified cost $47,403,071)			$	45,586,499

Short-Term Investments — 2.8%

	Interest
Description	(000’s omitted)		Value
Eaton Vance Cash Reserves Fund, LLC, 0.21%(2)	$	1,314	$	1,314,197
Total Short-Term Investments — 2.8% (identified cost $1,314,197)			$	1,314,197
Total Investments — 100.9% (identified cost $48,717,268)			$	46,900,696
Other Assets, Less Liabilities — (0.9)%			$	(413,667	)
Net Assets — 100.0%			$	46,487,029

The percentage shown for each investment category in the Portfolio of Investments is based on net assets.
At January 31, 2011, the concentration of the Portfolio’s investments in the various states, determined as a percentage of net assets, is as follows:
	California	15.7%
	New York	12.2%
	Pennsylvania	11.8%
	Others, representing less than 10% individually	61.2%
(1)	Build America Bonds. Represent taxable municipal obligations issued pursuant to the American Recovery and Reinvestment Act of 2009 or other legislation providing for the issuance of taxable municipal debt on which the issuer receives federal support.
(2)	Affiliated investment company available to Eaton Vance portfolios and funds which invests in high quality, U.S. dollar denominated money market instruments. The rate shown is the annualized seven-day yield as of January 31, 2011. Net income allocated from the investment in Eaton Vance Cash Reserves Fund, LLC for the fiscal year to date ended January 31, 2011 was $495.

2

The Portfolio did not have any open financial instruments at January 31, 2011.

The cost and unrealized appreciation (depreciation) of investments of the Portfolio at January 31, 2011, as determined on a federal income tax basis, were as follows:

Aggregate cost	$	48,759,609
Gross unrealized appreciation	$	173,743
Gross unrealized depreciation		(2,032,656	)
Net unrealized depreciation	$	(1,858,913	)

Under generally accepted accounting principles for fair value measurements, a three-tier hierarchy to prioritize the assumptions, referred to as inputs, is used in valuation techniques to measure fair value. The three-tier hierarchy of inputs is summarized in the three broad levels listed below.

•   Level 1 — quoted prices in active markets for identical investments

•   Level 2 — other significant observable inputs (including quoted prices for similar investments, interest rates, prepayment speeds, credit risk, etc.)

•   Level 3 — significant unobservable inputs (including a fund’s own assumptions in determining the fair value of investments)

In cases where the inputs used to measure fair value fall in different levels of the fair value hierarchy, the level disclosed is determined based on the lowest level input that is significant to the fair value measurement in its entirety. The inputs or methodology used for valuing securities are not necessarily an indication of the risk associated with investing in those securities.

At January 31, 2011, the hierarchy of inputs used in valuing the Portfolio’s investments, which are carried at value, were as follows:

	Quoted Prices in
	Active Markets for		Significant Other		Significant
	Identical Assets		Observable Inputs		Unobservable Inputs
Asset Description	(Level 1)		(Level 2)		(Level 3)		Total
Taxable Municipal Securities	$	—	$	45,586,499	$	—	$	45,586,499
Short-Term Investments		—		1,314,197		—		1,314,197
Total Investments	$	—	$	46,900,696	$	—	$	46,900,696

The Portfolio held no investments or other financial instruments as of October 31, 2010 whose fair value was determined using Level 3 inputs. At January 31, 2011, the value of investments transferred between Level 1 and Level 2, if any, during the fiscal year to date then ended was not significant.

For information on the Portfolio’s policy regarding the valuation of investments and other significant accounting policies, please refer to the Portfolio’s most recent financial statements included in its semiannual or annual report to shareholders.

Subsequent Events

As of the close of business on February 28, 2011, the Eaton Vance Build America Bond Fund withdrew its entire interest in the Portfolio in cash and securities. On March 11, 2011, the Portfolio terminated.

3

Item 2. Controls and Procedures

(a) It is the conclusion of the registrant’s principal executive officer and principal financial officer that the effectiveness of the registrant’s current disclosure controls and procedures (such disclosure controls and procedures having been evaluated within 90 days of the date of this filing) provide reasonable assurance that the information required to be disclosed by the registrant on this Form N-Q has been recorded, processed, summarized and reported within the time period specified in the Commission’s rules and forms and that the information required to be disclosed by the registrant on this Form N-Q has been accumulated and communicated to the registrant’s principal executive officer and principal financial officer in order to allow timely decisions regarding required disclosure.

(b) There have been no changes in the registrant’s internal controls over financial reporting during the fiscal quarter for which the report is being filed that have materially affected, or are reasonably likely to materially affect the registrant’s internal control over financial reporting.

Signatures

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Build America Bond Portfolio
By:	/s/ Cynthia J. Clemson
	Cynthia J. Clemson
	President

Date: March 24, 2011

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By:	/s/ Cynthia J. Clemson
	Cynthia J. Clemson
	President

Date: March 24, 2011

By:	/s/ Barbara E. Campbell
	Barbara E. Campbell
	Treasurer

Date: March 24, 2011

EX-99.CERT

Build America Bond Portfolio

Certification
Pursuant to Rule 302 of the Sarbanes-Oxley Act of 2003

I, Cynthia J. Clemson, certify that:

1. I have reviewed this report on Form N-Q of Build America Bond Portfolio;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the schedule of investments included in this report fairly present in all material respects the investments of the registrant as of the end of the fiscal quarter for which the report is being filed;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant and have:

     (a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

     (b) Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

     (c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report, based on such evaluation; and

     (d) Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officers and I have disclosed to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

     (a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize, and report financial information; and

     (b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

By:	/s/ Cynthia J. Clemson
	Cynthia J. Clemson
	President

Date: March 24, 2011

Build America Bond Portfolio

Certification
Pursuant to Rule 302 of the Sarbanes-Oxley Act of 2003

I, Barbara E. Campbell, certify that:

1. I have reviewed this report on Form N-Q of Build America Bond Portfolio;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the schedule of investments included in this report fairly present in all material respects the investments of the registrant as of the end of the fiscal quarter for which the report is being filed;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant and have:

     (a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

     (b) Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

     (c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report, based on such evaluation; and

     (d) Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officers and I have disclosed to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

     (a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize, and report financial information; and

     (b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

By:	/s/ Barbara E. Campbell
	Barbara E. Campbell
	Treasurer

Date: March 24, 2011