NEWS RELEASE

FOR IMMEDIATE RELEASE

ULTRA PETROLEUM REPORTS 2008 PROVED RESERVES OF 3.52 TCFE,

AN 18 PERCENT INCREASE, OR 21 PERCENT ON A PER SHARE BASIS, AND

ALL-IN F&D COST OF $1.39 PER MCFE WITH

470 PERCENT ORGANIC RESERVE REPLACEMENT RATIO

2008 proved reserves increase to 3.52 Tcfe from 2.98 in 2007

2008 total 3P reserves increase to 11.66 Tcfe from 10.74 Tcfe in 2007

2008 all-in F&D costs of $1.39 per Mcfe

Undrilled inventory grows to 5,570 locations

HOUSTON, Texas – February 17, 2009 – Ultra Petroleum Corp. (NYSE: UPL) today announced that its total proved oil and gas reserves for the year-ended December 31, 2008, were 3.52 trillion cubic feet of gas equivalent (Tcfe), an 18 percent increase from 2.98 Tcfe as of December 31, 2007. On a per share basis, the 2008 proved reserves increased 21 percent from 2007. The 2008 reserve replacement of 470 percent was achieved organically. Corporate finding and development costs in 2008 were an industry- leading $1.39 per Mcfe, inclusive of all capital costs. Capital costs during 2008 were $949.7 million. Finding and development costs mirror the company’s depletion rate. There were no required impairment expenses.

The total 3P reserves estimated by a third-party engineering consulting firm increased to 11.66 Tcfe at year-end 2008 an increase of 9 percent from 10.74 Tcfe at year-end 2007. As of December 31, 2008, the estimated future net cash flow discounted at 10 percent, or pre-tax PV-10, is $11.1 billion as compared to $10.0 billion at year-end 2007.

“The foundation of Ultra Petroleum that I don’t emphasize enough is the scale of what we own in one field in southwestern Wyoming - our nearly 12 Tcfe of reserves at the industry’s lowest cost structure. The most often mentioned challenge for energy companies today is resource capture to enable growth. At Ultra, we’ve met that challenge and have in excess of a 20 year inventory of high rate of return projects,” stated Michael D. Watford, Chairman, President and Chief Executive Officer. “And unlike many of our peers, Ultra’s 2008 proved reserves increased 18 percent despite a 23 percent decrease in SEC pricing,” Watford added.

The company’s inventory of low-risk, high rate-of-return natural gas drilling locations continues to grow. At year-end 2007 the number of undrilled locations in Ultra’s inventory was 5,300. In 2008, the company participated in 307 wells and ended the year with an undrilled inventory of 5,570 locations, an increase of almost 600 locations from 2007.

http://www.ultrapetroleum.com/pressr...