On Wednesday, 5 September 2012, executives of Ensco plc (NYSE: ESV) will ring the opening bell at the New York Stock Exchange in celebration of the offshore drilling company’s 25 th anniversary. “Ensco is at a key moment in its history,” said Chairman and CEO Dan Rabun. “We have a world-class offshore drilling fleet working in virtually every major basin around the globe. We’re rated number one in total customer satisfaction due to the dedication of our employees, and we will continue to grow as we take delivery of the six rigs we currently have under construction. This is definitely a time to celebrate and we look forward to our next 25 years.” Ensco will present at the Barclays Energy Conference in New York City on Wednesday, 5 September 2012, at 2:25 p.m. EDT. The presentation will be available live over the Internet at www.enscoplc.com by selecting Investors/Presentations and Webcasts. Please go to the website at least 15 minutes before the presentation to register, download and install any necessary audio software. A replay of the presentation will be available on Ensco’s website within twenty-four hours of the live presentation and remain available for 30 days. Ensco plc (NYSE: ESV) brings energy to the world as a global provider of offshore drilling services to the petroleum industry and was recently added to the S&P 500 Index. For 25 years, the company has focused on operating safely and exceeding customer expectations. Ensco is ranked #1 for total customer satisfaction with top honors in 13 of 17 categories in the most recent annual survey by EnergyPoint Research. Operating the world’s newest ultra-deepwater fleet and largest fleet of active premium jackups, Ensco has a major presence in the most strategic offshore basins across six continents. Ensco plc is an English limited company (England No. 7023598) with its registered office and corporate headquarters located at 6 Chesterfield Gardens, London W1J 5BQ. To learn more, visit our website at www.enscoplc.com. Statements contained in this press release that are not historical facts are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements include words or phrases such as “anticipate,” “believe,” “estimate,” “expect,” “intend,” “plan,” “project,” “could,” “may,” “might,” “should,” “will” and similar words. Such statements are subject to numerous risks, uncertainties and assumptions that may cause actual results to vary materially from those indicated. In addition to the numerous factors described above, you should also carefully read and consider “Item 1A. Risk Factors” in Part I and “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations” in Part II of our most recent annual report on Form 10-K, as updated in subsequent quarterly reports on Form 10-Q, which are available on the SEC’s website at www.sec.gov or in the Investor Relations section of our website at www.enscoplc.com . Each forward-looking statement speaks only as of the date of the particular statement, and we undertake no obligation to publicly update or revise any forward-looking statements, except as required by law.