KIRBY CORPORATION Contact: Steve Holcomb 713-435-1135

FOR IMMEDIATE RELEASE

KIRBY CORPORATION CONFIRMS 2005 THIRD QUARTER AND YEAR GUIDANCE IN THE AFTERMATH OF

Houston, Texas (September 13, 2005) – Kirby Corporation (“Kirby”) (NYSE:KEX) announced today that it is confirming its 2005 third quarter earnings guidance of $.65 to $.70 per share and 2005 year guidance of $2.50 to $2.60 per share. Kirby estimates the effects of Hurricane Katrina will be in the $.04 to $.05 per share range.

Joe Pyne, Kirby’s President and Chief Executive Officer, commented, “Our marine transportation and diesel engine services markets have remained strong during the 2005 third quarter. Hurricane Katrina caused no notable damage to Kirby’s fleet of 887 inland tank barges, 241 inland towboats or its four 35% owned offshore dry cargo barge and tug units. All waterways in the affected areas normally navigated by Kirby vessels are open to inland and offshore barge traffic with the exception of the Lock located in eastern , which connects the Mississippi River with the Gulf Intracoastal Waterway for movements eastbound to Mississippi, Alabama and Florida. Kirby is presently moving cargoes to ports east of New Orleans by diverting through the Baptiste Collette Bayou which bypasses eastern New Orleans. Movements along the Texas and southwestern Louisiana Gulf Intracoastal Waterway, Kirby’s major areas of marine transportation operation, are operating normally.”

Mr. Pyne further commented, “Substantially all of the petrochemical and refinery facilities serviced by Kirby and located in the impacted area of Katrina were either totally shutdown or production levels were significantly reduced as a result of the hurricane. Presently, most facilities are back in full operation or operating on a limited production basis. Several facilities south of New Orleans, and along the Mississippi and Alabama Gulf Coast, remain closed.”

Commenting on low water conditions on the Ohio River and , Mr. Pyne stated, “For several weeks prior to Katrina, Kirby had been light loading tank barges for destinations on the Ohio and lower Mississippi Rivers due to low water conditions on these rivers. Katrina brought much needed rainfall to the Ohio River Valley and temporarily alleviated the low water conditions; however, water levels have since begun to fall and we are currently light loading tank barges for upriver destinations.”

1 Kirby Corporation will present at Jefferies & Company Second Annual Shipping Conference at the Mandarin Oriental Hotel in New York on Thursday, September 15, 2005 at 11:00 a.m. Eastern Daylight Time. The audio only presentation will be broadcast live over the Internet and can be accessed at http://www.jefferies.com/0905shipping. The slide presentation for the Jefferies conference will be available on September 15th on Kirby’s website at http://www.kirbycorp.com. Replays will be available at the Jefferies website for 90 days.

Kirby Corporation, based in Houston, Texas, operates inland tank barges and towing vessels, transporting petrochemicals, black oil products, refined petroleum products and agricultural chemicals throughout the United States inland waterway system. Through the diesel engine services segment, Kirby provides after-market service for large medium-speed and high-speed diesel engines and reduction gears used in marine, power generation and railroad applications.

Statements contained in this press release with respect to the future are forward-looking statements. These statements reflect management’s reasonable judgment with respect to future events. Forward-looking statements involve risks and uncertainties. Actual results could differ materially from those anticipated as a result of various factors, including cyclical or other downturns in demand, significant pricing competition, unanticipated additions to industry capacity, changes in the Jones Act or in U.S. maritime policy and practice, fuel costs, interest rates, weather conditions, and the timing, magnitude and number of acquisitions made by Kirby. Forward-looking statements are based on currently available information and Kirby assumes no obligation to update any such statements. A list of additional risk factors can be found in Kirby’s annual report on Form 10-K for the year ended December 31, 2004, filed with the Securities and Exchange Commission.

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