The U.S. Postal Service® currently has two 55-cent fundraising or "semipostal" stamps available for purchase at Post Offices™, online at The Postal Store®, and by toll-free phone order at 1-800 STAMP-24: the Breast Cancer Research stamp and Save Vanishing Species stamp.

The price of a semipostal stamp pays for the First-Class™ single-piece postage rate in effect at the time of purchase plus an amount to fund causes that have been determined to be in the national public interest. By law, revenue from sales (minus postage and the reasonable reimbursement of costs to the Postal Service) is to be transferred to a selected executive agency or agencies.

Breast Cancer Research Stamp
The Breast Cancer Research semipostal was issued on July 29, 1998, at a first day ceremony held at the White House. It was the first semipostal in U.S. history.

As of October, 2012, the stamp has raised over $76.3 million for breast cancer research. By law, 70 percent of the net amount raised is given to the National Institutes of Health and 30 percent is given to the Medical Research Program at the Department of Defense.

Designed by Ethel Kessler of Bethesda, MD, the stamp features the phrases, "Fund the Fight" and "Find a Cure" and an illustration of a mythical "goddess of the hunt" by Whitney Sherman of Baltimore.

Save Vanishing Species Stamp
The U.S. Postal Service issued its fourth semipostal stamp – Save Vanishing Species – on September 20, 2011. These stamps provide a convenient way for the American public to contribute to the protection of threatened and vanishing species. 

The Postal Service donates the net proceeds via the U. S. Fish and Wildlife Service to support the Multinational Species Conservation Funds. These funds are dedicated to improving the status of wildlife that includes, among other animals, tigers, African and Asian elephants, rhinos, great apes, and marine turtles.  As of October, 2012, over $1.74 million has been raised for the cause.

Designed by Nancy Stahl, the stamp features an illustration of a tiger cub. The phrases “Save Vanishing Species” and “Amur tiger cub” appear on the left side of the stamp. Stahl drew her inspiration for the stamp art and silhouettes from photographs of wildlife.