Mt. Holly, SC

Mt Holly image

The most modern smelter in U.S. and billet supplier

Century’s Mt. Holly aluminum smelter has a production capacity of 229,000 metric tonnes of aluminum per year. Mt. Holly is the most advanced plant of its kind in the United States, a pacesetter in production efficiency, energy utilization and environmental protection.

The smelter contains casting equipment used to cast molten aluminum into standard-grade ingot, HDC ingot, extrusion billet and other value-added primary aluminum products. Value-added primary aluminum products are sold at a premium to standard-grade primary aluminum.

The Mt. Holly plant has become an industry leader in production efficiency, energy utilization and environmental control, and proudly holds the title of the first primary aluminum plant in the world to be registered completely to the ISO 9001 Quality System Standard.

Mt Holly image
About Our Mt. Holly Facility image

About Our Mt. Holly Facility




Rated Primary Aluminum Capacity

229,000 mtpy

Reduction Facilities

  • Two Alcoa-designed potlines with a total of 360 reduction cells
  • Most recently constructed aluminum reduction facility in the U.S.
  • Carbon Facilities
  • Casthouse Facilities

Power Supply

South Carolina Public Service Authority (Santee Cooper)

Quality Certification

Mt. Holly is quality certified to the ISO 9001:2015 standard.


For information on products made at our Mt. Holly facility, click here.


Billet, Horizontal Direct Chill (HDC) Ingot, T-Ingot, and Slab


  • 35-pound ingots 30.5 inches long
  • Alloys: Pure, EC, 1050, 1060, 1100, 1145, 1200, 1235, 1350, 1435, 3003, 3004, 3005, 3102, 3104, 3105, 6004, 6005, 6006, 6060,6061, 6063, 6101, 6105, 6151, 6162, 6351, 6463, Rotor, A306.3, 319.2, C355.2, 356.1, 356.2, A356.2, A357, C357


  • 12 X 34 inches – 33.4 pounds per inch
  • Alloys: P1020A, P0610, A306.3, 319.2, C355.2, A356.1, A356.2, A357


  • Air Slip and NuMax Technology
  • Lengths – Up to 288 inches (7.3 meters) cropped
  • Diameters – 6.0 inches (15.24 cm), 6.5 inches (16.51 cm), 7.0 inches (17.78 cm), 8.0 inches (20.32 cm), 9.0 inches (22.86 cm), 10 inches (25.40 cm), 14 inches (35.56 cm)
  • Up to 70 alloy combinations, custom ordering available


  • 1XXX, 2XXX, 3XXX, 5XXX, and 6XXX
  • Up to 70 alloy combinations, custom ordering available