Hornbeck Offshore Announces Delivery, Triple Certification of World’s Largest Supply Vessel

January 6, 2009 — Covington, Louisiana — Hornbeck Offshore Services, Inc. (NYSE:HOS) has introduced the HOS Centerline, a Jones Act qualified, 370’ multi-purpose support vessel (MPSV) to its fleet. This HOS 370 design, with an 8,000+ deadweight-ton capacity represents the largest and most diverse DP-2 classed offshore supply vessel available today. The HOS Centerline is the only vessel in the world to have received certifications by the United States Coast Guard allowing operations as a supply vessel, industrial/construction vessel and as a petroleum and chemical tanker.

The HOS Centerline was added to Hornbeck's fleet in February 2009 and achieved its multi-certifications under Subchapters “L’, “I”, “D” and “O” in October, 2009. Her sister-vessel, HOS Strongline will join the fleet in early 2010 and is expected to receive the same regulatory pedigree. Both vessels will be based at the company’s shore base facility, HOS Port, located in Port Fourchon, Louisiana. The company acquired the HOS Port facility and its heavy lift capabilities in order to accommodate its growing fleet of large dimension vessels, including the HOS Centerline and HOS Strongline.

Among their work within the offshore energy industry, these unique vessels have the capacity to transport more than 30,000 barrels of liquid drilling mud and fuel to and from exploration, development and production projects. Positive displacement pumping systems allow the vessels to provide a consistent transfer of product even at installations with large air gaps. The HOS Centerline boasts a self-contained mixing and cleaning system that significantly reduces the risk of drilling fluid collapse as well as reduces the time necessary to clean storage tanks, which is a cost normally borne by its customers. Mud mixers utilize low inertia paddles to reduce the fall-out of the mud and provide for a consistent mix. The vessel’s significant size, 8,400 kw of available propulsion, power and DP-2 capability allows it to continue cargo transfer operations during sea and weather conditions that prevent smaller vessels from working.

With its subchapter ”D” and “O” certifications, the HOS Centerline can carry crude oil as well as other flammable and combustible cargoes in significant quantities from offshore drilling and production sites. The vessels offer 18 tanks with three separate segregations that allow the transport of three separate products at the same time. This feature makes the vessel an excellent platform for various well test, flow-back and dewatering projects in deepwater and ultra-deepwater. The vessel can also be utilized for emergency export of crude oil and other fluids during times of or following disruptions, such as hurricanes.

The HOS 370-class cargo deck dimension is 240 feet x 58 feet (1,287m2) and complemented by an additional 30’ x 58’ of covered deck space, unparalleled in the industry. The vessels have multi-functional ISO sockets integrated into the bow to accept standard sized containers to increase loading productivity and eliminate the use of traditional chains and binders. The HOS Centerline has accommodations for up to 78 personnel, in excess of the vessel’s crew. The large deck and ample quarters provide an excellent platform for subsea construction operations.

For further specifications and details on the HOS Centerline and HOS Strongline, see attached, or visit www.hornbeckoffshore.com

Hornbeck Offshore Services, Inc. is a leading provider of technologically advanced, new generation offshore supply vessels in the U.S. Gulf of Mexico and in select other domestic and international markets, and is a leading short-haul transporter of petroleum products through its coastwise fleet of ocean-going tugs and tank barges in the northeastern U.S., the domestic Gulf of Mexico, the Great Lakes and in Puerto Rico. Hornbeck Offshore currently owns a fleet of over 80 vessels primarily serving the energy industry.

Forward-Looking Statements

This press release contains “forward-looking statements,” as contemplated by the Private Securities Litigation Reform Act of 1995, in which the Company discusses factors it believes may affect its performance in the future. Forward-looking statements are all statements other than historical facts, such as statements regarding assumptions, expectations, beliefs and projections about future events or conditions. You can generally identify forward-looking statements by the appearance in such a statement of words like “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “might,” “plan,” “potential,” “predict,” “forecast,” “project,” “should” or “will” or other comparable words or the negative of such words. The accuracy of the Company’s assumptions, expectations, beliefs and projections depend on events or conditions that change over time and are thus susceptible to change based on actual experience, new developments and known and unknown risks. The Company gives no assurance that the forward-looking statements will prove to be correct and does not undertake any duty to update them.