Petrohawk Doubles Proved Reserves to 2.75 Tcfe

Petrohawk Energy's proved oil and gas reserves at December 31, 2009 are estimated at 2.75 trillion cubic feet of natural gas equivalent (Tcfe). Proved reserves increased over 1.5 Tcfe over year end 2008, pro forma for the sale of the Company's Permian Basin properties in October 2009. Proved reserves, pro forma for the sale of the Permian Basin properties, grew 122% year over year. Production, pro forma for the sale of the Permian Basin properties, grew 76% year over year. Petrohawk's estimated proved reserves at December 31, 2009 were prepared by the independent reserve engineering firm Netherland, Sewell and Associates, Inc. in accordance with Securities and Exchange Commission ("SEC") guidelines.

"Petrohawk experienced significant growth during 2009 in both production and reserves thanks to our successful development program and an asset portfolio that was resilient during the year's low price environment for natural gas," said Floyd C. Wilson, Chairman and Chief Executive Officer. "While our growth in proved reserves was impressive, these reserves were booked using SEC guidelines for offset locations, taking into account full-year average pricing and governed by development scheduling criteria of five years or less, and are equally impressive when viewed on historical rules. The results of our 2009 drilling program have a tremendous impact on our net asset value. As never before, the stage is set for an HK multi-year development plan designed to continue to deliver double-digit production and reserve growth with an overarching focus on free cash flow."

The Company increased proved developed reserves by approximately 34% and proved undeveloped reserves by 227%. Petrohawk replaced 920% of production, producing 183 Bcfe in 2009, and divested 171 Bcfe of proved reserves during the year. In 2009, organic finding and development costs, excluding land and seismic costs, were the lowest in Petrohawk's history, at $0.68 per Mcfe, with $1.15 billion in capital expenditures.

The Company's new reserves-to-production ratio (R/P, defined as proved reserves of 2.75 Tcfe divided by 2009 pro forma production of 173 Bcfe) is 15.9 years.

Of Petrohawk's 2.75 Tcfe of proved reserves (98% natural gas), approximately 1.96 Tcfe were added through the drillbit in 2009. Approximately 1.5 Tcfe were added in the Haynesville Shale with 176 wells drilled (73 operated and 103 non-operated), 294 Bcfe in the Eagle Ford Shale with 26 wells drilled (24 operated and 2 non-operated), 178 Bcfe in the Fayetteville Shale with 362 wells drilled (35 operated and 327 non-operated), and 18 Bcfe with 62 wells drilled in other areas. Proved reserves are 33% proved developed, compared to 56% proved developed associated with year-end 2008 reserves. Revisions, including pricing-related revisions accounted for a reduction of 277 Bcfe.

For year-end 2009, new SEC rules were implemented requiring that reserve calculations be based on the unweighted average first-day-of-the-month prices for the prior twelve months, as contrasted with the previous method which utilized period end prices. The prices under the new rules were $3.87 per Mmbtu for natural gas and $61.18 per barrel for oil adjusted for energy content, quality and basis differentials. Under the new rules, the pre-tax discounted (10%) present value of the year-end 2009 reserves was $1.5 billion. Using prices on December 31, 2009 of $5.79 per Mmbtu for natural gas and $79.36 per barrel for oil with similar adjustments, the pre-tax discounted (10%) present value of year-end proved reserves would have been $4.4 billion with proved reserves of 3.1 Tcfe.

Petrohawk's current estimate of the Company's risked resource potential, revised for the conversion of 1.8 Tcfe of unproved reserves to proved, is 31.0 Tcfe.

Fourth Quarter and Full Year 2009 Performance

Petrohawk's fourth quarter 2009 production averaged 598 Mmcfe/d, 28 Mmcfe/d above the midpoint of the Company's stated guidance, and full year 2009 production averaged 502 Mmcfe/d (475 Mmcfe/d pro forma for the sale of the Permian Basin properties). Fourth quarter production represented a 17% increase over third quarter 2009 and an 81% increase over the same period in 2008 on a pro forma basis. The Company exited 2009 producing approximately 600 Mmcfe/d compared to a pro forma exit rate of 366 Mmcfe/d in 2008.

All costs for the fourth quarter and the full year 2009 are expected to be in line with ranges Petrohawk published at the beginning of 2009, with the exception of general and administrative expenses. During the fourth quarter, the Company expects to record legal expenses in excess of what had been projected by approximately $18 million. The final amount will be reported on Petrohawk's Form 10K to be filed later this month.

2010 Production Guidance and Hedging Update

Petrohawk has set first quarter 2010 production guidance between 615 and 625 Mmcfe/d, and full year 2010 production guidance remains between 670 and 680 Mmcfe/d, a 36% year over year increase. Approximately 68% of expected 2010 production is hedged with natural gas collars with floors averaging $5.83 per Mcf and ceilings averaging $9.21 per Mcf. Additionally, over 50% of 2011 expected production is currently hedged at floors averaging $5.55 per Mcf and ceilings averaging $9.66 per Mcf.