Less common - 3.4% of US donors
AB-positive is the universal red-cell recipient. Carrying both A and B antigens plus the Rh-D antigen means the AB-positive immune system does not produce antibodies against any of these, allowing it to accept red cells from all 8 blood types. However, AB-positive can only donate red cells to other AB-positive recipients. Separately, AB is also the universal plasma donor because AB plasma contains neither anti-A nor anti-B antibodies.
Antigens present
A antigen, B antigen, Rh-D antigen
Antibodies produced
None (no anti-A, no anti-B)
Antigens are proteins on the surface of red blood cells. The ABO antibodies (anti-A and anti-B) are naturally occurring - present from infancy against whichever A or B antigen you lack. The Rh anti-D antibody is different: Rh-negative people do not carry it from birth and only form it after exposure to Rh-positive blood through transfusion or pregnancy (sensitisation), which is why anti-D immunoglobulin is given to prevent it. When incompatible blood is transfused, antibodies bind to foreign antigens and trigger a haemolytic reaction.
Select your blood type:
Can donate red cells to:
1 compatible type
Can receive red cells from:
Universal recipient - can receive from all 8 types
| Population | Frequency |
|---|---|
| US blood donors (Red Cross estimate) | 3.4% |
| Global population (estimate) | 5.1% |
AB-positive is found in approximately 3.4% of US donors and about 5.1% globally. It is less common than O, A, and B types, but the rarest of the 8 major types is AB-negative (0.6%). AB types are more prevalent in East Asian populations (particularly Japan and Korea) and less common in sub-Saharan African populations. Despite its rarity, AB-positive individuals are extremely valuable plasma donors.
AB-type individuals carry both A and B antigens. Some large studies suggest AB and B blood groups are associated with modestly higher risk of venous thromboembolism compared to O. These are statistical population associations and should not influence personal medical decisions. A notable clinical point: AB-positive individuals are the only universal plasma donors. Their plasma (containing neither anti-A nor anti-B antibodies) can be given to any patient in an emergency without blood typing. Blood banks frequently need AB-positive (and AB-negative) plasma donors.
Note: Associations between blood type and disease risk are from observational studies and are not deterministic. They do not change your clinical management. Cite any specific associations with your clinician.
AB-positive mothers are Rh-positive. Rh incompatibility is not a pregnancy concern for Rh-positive mothers. Your AB blood type also means your baby will inherit at least one of A or B from you, but ABO incompatibility between mother and fetus is generally mild. If you are AB-positive and pregnant, your blood type does not add specific Rh or ABO-related risk. Your obstetrician will still test your blood type at the first antenatal visit as part of routine care.
Full Rh factor pregnancy guide +AB-positive is the universal organ recipient: organs from any of the 8 ABO types can be transplanted into an AB-positive patient based on ABO compatibility alone. However, HLA matching and crossmatch testing still matter - ABO compatibility is a necessary but not sufficient condition for transplant. As an organ donor, AB-positive can only donate to other AB-positive recipients. If you are AB-positive and want to help as a living donor, note that your compatible recipient pool is limited to AB+ patients.
ABO compatibility for organ transplant follows the same rules as transfusion - AB+ can donate organs to: AB+. However, HLA tissue matching and crossmatch testing are also required, and sensitisation from prior transfusions or pregnancies can restrict compatibility further.
Full organ transplant guide +AB plasma (both AB+ and AB-) contains neither anti-A nor anti-B antibodies. This makes AB the universal plasma donor - AB plasma can be given to any patient regardless of blood type. This is the inverse of the red-cell rule (where O-negative is universal). If you are AB-positive, plasma donation is one of your most impactful contributions to the blood supply. Plasma can be donated every 28 days, more frequently than whole blood.
Note: Plasma compatibility rules are the inverse of red-cell rules because plasma carries antibodies, not antigens. AB plasma is the universal plasma donor.
Plasma compatibility chart +Updated 2026-04-27