Patterson-UTI Reports Drilling Activity for May 2012

PATTERSON-UTI ENERGY, INC.

today reported that for the month of May 2012, the Company had an average of 223 drilling rigs operating, including 223 rigs in the United States and no rigs in Canada. For the two months ended May 31, 2012, the Company had an average of 225 drilling rigs operating, including 225 rigs in the United States and no rigs in Canada. Average drilling rigs operating reported in the Company's monthly announcements represent the average number of the Company's drilling rigs that were operating under a drilling contract. The Company cautioned that numerous factors in addition to average drilling rigs operating can impact the Company's operating results and that a particular trend in the number of drilling rigs operating may or may not indicate a trend in or be indicative of the Company's financial performance. The Company intends to continue providing monthly updates on drilling rigs operating shortly after the end of each month.