Total said it made a "significant" discovery in the North Platte prospect in the Gulf of Mexico. The French company said it encountered "several hundred feet of net oil pay" in the region.
"Total estimates this discovery can have a potential of several hundred million barrels of oil," it said in a statement. "Further appraisal will be needed to confirm its size and commerciality."
North Platte lies in 4,400 of water. The company said its well was drilled to a depth of 34,500 feet.
The U.S. Department of Interior's Bureau of Ocean Energy Management last month conducted lease sale 229 in New Orleans, putting more than 20 million gulf acres on the auction block.
The BOEM estimated the lease could result in the production of, on average, 150 million barrels of oil and 730 billion cubic feet of natural gas.