Exhibit 99.1

FOR IMMEDIATE RELEASE:

American Midstream Partners, LP Reports Financial Results for the

2011 Fourth Quarter and Full Year

DENVER, CO –March 12, 2012–American Midstream Partners, LP (NYSE: AMID) today reported financial results for the 2011 fourth quarter and full year ending December 31, 2011.

Total revenue for the fourth quarter of 2011 was $57.4 million, an increase of $0.9 million, or 1.6%, compared to $56.5 million in the prior year period. Total revenue for the full year 2011 was $244.7 million compared to $211.9 million for the prior year ending December 31, 2010.

Gross margin for the fourth quarter of 2011 was $13.6 million, an increase of $2.6 million, or 23.6%, compared to $11.0 million in the prior year period. The increase in the fourth quarter was due principally to higher throughput volume and associated natural gas liquids (“NGL”) production from owned processing plants, improved processing and percent-of-proceed (“POP”) margins from higher NGL and condensate prices and higher throughput in our Gathering and Processing segment. We also achieved incremental gross margin of $1.1 million associated with our acquisition of a 50% undivided, non-operating, interest in the Burns Point Plant effective November 1, 2011. A $0.2 million increase in construction, operating and maintenance agreement (“COMA”) income contributed to the increase.

Gross margin for the full year 2011 was $45.9 million, an increase of $7.8 million, or 20.5%, compared to $38.1 million for the full year 2010. The increase in the full year was due principally to higher throughput volume and associated NGL production from owned processing plants, improved processing and POP margins from higher NGL and condensate prices and higher throughput in our Gathering and Processing segment. Incremental gross margin of $1.1 million associated with the Burns Point acquisition and a $0.5 million increase in COMA income contributed to the increase.

Adjusted EBITDA for the fourth quarter of 2011 was $6.1 million, an increase of $0.4 million, or 7.0%, compared to $5.7 million in the prior year period. Adjusted EBITDA for the full year 2011 was $21.0 million, an increase of $2.7 million, or 14.8%, compared to $18.3 million for the full year 2010.

Net income for the fourth quarter of 2011 was $0.2 million, compared to net loss of $1.0 million in the prior year period. Net loss for the full year 2011 was $11.7 million, compared to net loss of $8.6 million for the full year 2010. Limited partners’ net income per common unit and subordinated unit for the fourth quarter of 2011 was $0.02, compared to limited partners’ net loss per common unit and subordinated unit of $0.18 in the prior year period. Limited partners’ net loss per common unit and subordinated unit for the full year 2011 was $1.64, compared to limited partners’ net loss per common unit and subordinated unit of $1.66 for the full year 2010.

Distributable cash flow for the fourth quarter of 2011 was $4.5 million. Distributable cash flow for the full year 2011 was $13.2 million.

Commenting on the quarter and full year results, Brian Bierbach, President and Chief Executive Officer said, “We finished 2011 with a strong quarter. The operational issues impacting some of our Gathering and Processing assets in the third quarter were resolved with no meaningful impact on our fourth quarter gross margin. We completed the Burns Point transaction, and that asset has performed to our expectations. We also announced our first distribution increase.”

“Our SG&A costs were slightly higher than expected in the fourth quarter and full year 2011, largely due to additional public company related expenses and costs incurred to address and resolve the third quarter operational issues.”

“As a public company, we have been able to enhance and build upon our customer relationships. We continue to remain competitive in our markets despite a weak natural gas environment, and our financial performance is a reflection of this. Looking forward, we are optimistic in our ability to continue pursuing growth through commercial, development and acquisition opportunities.”

REVIEW OF SEGMENT PERFORMANCE

Gross margin for our two segments increased to $13.6 million in the fourth quarter of 2011 from $11.0 million in the prior year period. For the full year 2011, gross margin for our two segments was $45.9 million compared to $38.1 million for the full year 2010.

Gathering and Processing – The Gathering and Processing segment includes natural gas transportation and gathering, natural gas processing and treating, and selling or delivering natural gas and NGLs to various markets and pipeline systems.

Segment gross margin for Gathering & Processing was $9.5 million for the fourth quarter of 2011, compared with $7.1 million for the prior year period. For the full year 2011, Gathering and Processing segment gross margin was $32.2 million, compared to $24.6 million for the full year 2010.

For the Gathering & Processing segment, total natural gas throughput volumes averaged 320.0 million cubic feet (“MMcf”) per day and processed NGLs averaged 63,100 gallons per day for the fourth quarter of 2011, compared to 201.1 MMcf per day of natural gas and 46,400 gallons per day of processed NGLs for the prior year period. Total natural gas throughput volumes for the full year 2011 averaged 250.9 MMcf per day versus 175.6 MMcf per day for the full year 2010. Processed NGLs averaged 54,500 gallons per day for the full year 2011 versus 34,100 gallons per day for the full year 2010.

The increase in segment gross margin for the fourth quarter and full year 2011 was primarily due to higher throughput volume and associated NGL production at our Bazor Ridge processing plant, increased throughput volume on our Quivira system, higher realized NGL prices associated with our POP and elective processing agreements and incremental margin associated with the acquisition of our 50% interest in the Burns Point Plant in November 2011.

Transmission – The Transmission segment transports and delivers natural gas from producing wells, receipt points or pipeline interconnects for shippers.

Segment gross margin for Transportation was $4.1 million for the fourth quarter of 2011, compared with $3.9 million for the prior year period. For the full year 2011, Transmission segment gross margin was $13.7 million, compared to $13.5 million for the full year 2010.

Commenting on the two segments, Mr. Bierbach said, “We continue to see volume stability in our Gathering and Processing segment despite the low natural gas price environment. While some areas are witnessing lower drilling activity, existing wells are producing with few shut-ins. Additionally, liquids-rich plays around many of our systems are providing incremental volumes of associated gas, and we continue to pursue commercial opportunities targeting these plays.”

“Our Transmission segment has directly benefited from the natural gas environment. Our assets provide low-cost natural gas to utility and petrochemical customers in the southeast United States. We are seeing increased demand in these end markets through higher gas utilization and expansion projects near our systems.”

“We are also seeing attractive development opportunities in our area that leverage our existing assets in both the Gathering and Processing and the Transmission segments. We have been working with customers to provide midstream solutions for their drilling programs in conventional Gulf Coast areas and new plays like the Tuscaloosa Marine Shale and the Lower Smackover.”

Conference Call

American Midstream will conduct a conference call and webcast to discuss its fourth quarter and full year financial results on Tuesday, March 13, 2012, at 1:00 p.m. Eastern Time. The call may be accessed live at the investor relations section of the American Midstream website at www.AmericanMidstream.com. The live call may also be accessed by dialing 800-659-1942 for domestic users or 617-614-2710 for international users. The passcode for both phone numbers is 97383440.

A replay of the audio webcast will be available shortly after the call on American Midstream’s website. A telephonic replay will be available through April 15, 2012 by dialing 888-286-8010 for domestic users or 617-801-6888 for international users. The passcode for both phone numbers is 46891526.

Non-GAAP Financial Measures

This press release, and the accompanying tables, include both financial measures in accordance with U.S. generally accepted accounting principles, or GAAP, as well as non-GAAP financial measures, including “Adjusted EBITDA,” “gross margin” and “distributable cash flow.” The tables attached to this press release include reconciliations of these non-GAAP financial measures to the nearest GAAP financial measures. In addition an “Explanation of Non-GAAP Financial Measures” is set forth in Appendix A attached to this press release.

About American Midstream Partners

Denver-based American Midstream Partners is a growth-oriented limited partnership formed to own, operate, develop and acquire a diversified portfolio of natural gas midstream energy assets. The company provides midstream services in the Gulf Coast and Southeast regions of the United States. For more information about American Midstream Partners, visit www.AmericanMidstream.com.

Forward Looking Statements

This press release includes forward-looking statements. These statements relate to, among other things, projections of operational volumetrics and improvements, growth projects, cash flows and capital expenditures. We have used the words “anticipate”, “believe”, “could”, “estimate”, “expect”, “intend”, “may”, “plan”, “predict”, “project”, “should”, “will”, “potential” and similar terms and phrases to identify forward-looking statements in this press release. Although we believe the assumptions upon which these forward-looking statements are based are reasonable, any of these assumptions could prove to be inaccurate and the forward-looking statements based on these assumptions could be incorrect. Our operations involve risks and uncertainties, many of which are outside our control, and any one of which, or a combination of which, could materially affect our results of operations and whether the forward-looking statements ultimately prove to be correct. Actual results and trends in the future may differ materially from those suggested or implied by the forward-looking statements depending on a variety of factors which are described in greater detail in our filings with the SEC. Please see our Risk Factor disclosures included in our prospectus dated July 26, 2011 that was filed with the SEC on July 27, 2011. All future written and oral forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the previous statements. We undertake no obligation to update any information contained herein or to publicly release the results of any revisions to any forward-looking statements that may be made to reflect events or circumstances that occur, or that we become aware of, after the date of this press release.

American Midstream Partners, LP and Subsidiaries

Unaudited Consolidated Balance Sheets

(In thousands except unit amounts)

American Midstream Partners, LP and Subsidiaries

Unaudited Consolidated Statements of Operations

(In thousands, except per unit amounts)

American Midstream Partners, LP and Subsidiaries

Reconciliation of Net Income to Adjusted EBITDA

(In thousands)

Reconciliation of Adjusted EBITDA to Distributable Cash Flow

(In thousands)

Reconciliation of Net Cash Flows from Operating Activities to Distributable Cash Flow

(In thousands)

Reconciliation of Gross Margin to Net Income

(In thousands)

Appendix A

Note About Non-GAAP Financial Measures

Gross margin, adjusted EBITDA and distributable cash flows are all non-GAAP financial measures. Each has important limitations as an analytical tool because it excludes some, but not all, items that affect the most directly comparable GAAP financial measures. Management compensates for the limitations of these non-GAAP measures as analytical tools by reviewing the comparable GAAP measures, understanding the differences between the measures and incorporating these data points into management’s decision-making process.

You should not consider any of gross margin, adjusted EBITDA or distributable cash flow in isolation or as a substitute for analysis of our results as reported under GAAP. Because gross margin, adjusted EBITDA and distributable cash flow may be defined differently by other companies in our industry, our definitions of these non-GAAP financial measures may not be comparable to similarly titled measures of other companies, thereby diminishing their utility.

Adjusted EBITDA is a measure used by our management and by external users of our financial statements such as investors, commercial banks, research analysts and others, to assess:

We define adjusted EBITDA as net income, plus interest expense, income tax expense, depreciation expense, certain non-cash charges such as non-cash equity compensation, unrealized losses on commodity derivative contracts and selected charges that are unusual or non-recurring, less interest income, income tax benefit, unrealized gains on commodity derivative contracts, amortization of commodity put purchase costs and selected gains that are unusual or nonrecurring. The GAAP measure most directly comparable to adjusted EBITDA is net income.

Distributable cash flow is a significant performance metric used by us and by external users of our financial statements, such as investors, commercial banks and research analysts, to compare basic cash flows generated by us to the cash distributions we expect to pay our unitholders. Using this metric, management and external users of our financial statements can quickly compute the coverage ratio of estimated cash flows to planned cash distributions. Distributable cash flow is also an important financial measure for our unitholders since it serves as an indicator of our success in providing a cash return on investment. Specifically, this financial measure indicates to investors whether we are generating cash flow at a level that can sustain or support an increase in our quarterly distribution rates. Distributable cash flow is also a quantitative standard used throughout the investment community with respect to publicly traded partnerships and limited liability companies because the value of a unit of such an entity is generally determined by the unit’s yield (which in turn is based on the amount of cash distributions the entity pays to a unitholder). Distributable cash flow will not reflect changes in working capital balances.

We define distributable cash flow as adjusted EBITDA plus interest income, less cash paid for interest expense, integrity management costs and maintenance capital expenditures. The GAAP measure most directly comparable to distributable cash flow is net cash flows from operating activities.

Gross margin and segment gross margin are metrics that we use to evaluate our performance. We define segment gross margin in our Gathering and Processing segment as revenue generated from gathering and processing operations less the cost of natural gas, NGLs and condensate purchased. Revenue includes revenue generated from fixed fees associated with the gathering and treating of natural gas and from the sale of natural gas, NGLs and condensate resulting from gathering and processing activities under fixed-margin and percent-of-proceeds arrangements. The cost of natural gas, NGLs and condensate includes volumes of natural gas, NGLs and condensate remitted back to producers pursuant to percent-of-proceeds arrangements and the cost of natural gas purchased for our own account, including pursuant to fixed-margin arrangements.

We define segment gross margin in our Transmission segment as revenue generated from firm and interruptible transportation agreements and fixed-margin arrangements, plus other related fees, less the cost of natural gas purchased in connection with fixed-margin arrangements.

We define gross margin as the sum of our segment gross margin for our Gathering and Processing and Transportation segments.

Effective January 1, 2011, we changed our gross margin and segment gross margin measure to exclude unrealized mark-to-market adjustments related to our commodity derivatives. For the year ended December 31, 2011, $0.8 of unrealized losses was excluded from gross margin and the Gathering and Processing segment gross margin.

Effective April 1, 2011, we changed our gross margin and segment gross margin measure to exclude realized gains and losses associated with the early termination of commodity derivative contracts. For the year ended December 31, 2011, $3.0 million in realized losses was excluded from gross margin and the Gathering and Processing segment gross margin.