Probability of Having O-Negative Blood Type

O-negative blood is found in approximately 6.5% of the US population, making it relatively rare. It is known as the "universal donor" type because O-negative red blood cells can be safely transfused to patients of any blood type, making it critically important in emergency situations when there's no time to type a patient's blood.

Blood type distribution in the US is approximately: O+ (37.4%), A+ (35.7%), B+ (8.5%), AB+ (3.4%), O- (6.6%), A- (6.3%), B- (1.5%), AB- (0.6%). Distribution varies by racial and ethnic group. Type O is more common in Hispanic and Native American populations, while type B is more common in Asian and African American populations.

Because of its universal compatibility, O-negative blood is always in high demand and frequently in short supply. Only about 7% of blood donors are O-negative, but O-negative blood represents about 13% of hospital blood use. If you have O-negative blood, you are an especially valuable donor. The American Red Cross recommends eligible donors give blood every 56 days (for whole blood) or more frequently through platelet or power red donations.