United States one-dollar bills (and other United States banknotes) are primarily composed of cotton and linen. The Bureau of Engraving and Printing uses a unique blend of 75% cotton and 25% linen to create a strong and durable paper substrate for the bills. This blend was chosen for its strength, longevity, and resistance to counterfeiting.

The cotton and linen fibers are carefully processed and mixed to achieve a consistent texture. The paper undergoes several steps of processing, including bleaching, calendaring, and sizing. These processes ensure the paper's strength, smoothness, and ability to absorb ink and resist wear.

The Bureau of Engraving and Printing takes stringent measures to ensure the quality and security of the paper used for one-dollar bills and other banknotes. The paper contains microfibers, security threads, and watermarks that serve as anti-counterfeiting measures, helping to protect the integrity and reliability of the currency.