Rarest of the 8 major types - 0.6% of US donors
AB-negative is the rarest of the 8 major blood types, found in approximately 0.6% of US donors. Like AB-positive, AB-negative people produce no anti-A or anti-B antibodies and can receive red cells from any Rh-negative donor. But most critically, AB-negative plasma donors are among the rarest and most needed contributors to the blood supply - AB plasma is universally compatible regardless of Rh type.
Antigens present
A antigen, B antigen (no Rh-D)
Antibodies produced
None naturally (anti-D only if sensitised)
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:
2 compatible types
Can receive red cells from:
4 compatible types
| Population | Frequency |
|---|---|
| US blood donors (Red Cross estimate) | 0.6% |
| Global population (estimate) | 0.9% |
AB-negative is found in approximately 0.6% of US donors and about 0.9% of the global population. This makes it the rarest of the 8 common blood types. In a blood bank with 1,000 units on the shelf, you would expect fewer than 10 to be AB-negative. Blood banks must carefully manage AB-negative stocks. If you are AB-negative, your donation - whether whole blood or plasma - is extraordinarily valuable.
AB-negative individuals have both A and B antigens but lack Rh-D. From a clinical standpoint, being AB-negative means that as a recipient you can receive red cells from any Rh-negative donor (A-, B-, O-, AB-) - giving you a relatively broader Rh-negative pool compared to more restricted types like O-negative (which can only receive from O-). The dual role as both a relatively flexible recipient and a critical plasma donor makes AB-negative individuals uniquely valuable to blood banks.
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-negative mothers are Rh-negative. If the father is Rh-positive, the baby may be Rh-positive, creating risk of Rh sensitisation. Anti-D immunoglobulin (RhoGAM) prophylaxis is offered routinely and is highly effective. Being AB-type means your baby will inherit either A or B from you, but ABO incompatibility between mother and baby is rarely clinically significant. The key concern for AB-negative mothers is Rh status - ensure your obstetrician is aware and anti-D prophylaxis is arranged.
Full Rh factor pregnancy guide +AB-negative organ donors can give organs to AB-positive or AB-negative recipients only. As an AB-negative recipient, you can receive organs from A-, B-, O-, or AB- donors. This gives AB-negative patients a reasonable Rh-negative donor pool to choose from. The rarity of AB-negative blood type overall means longer wait times on transplant lists are a real possibility. Living donor evaluation is strongly recommended.
ABO compatibility for organ transplant follows the same rules as transfusion - AB- can donate organs to: AB+, 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-negative plasma, like AB-positive plasma, is universally compatible. AB plasma contains neither anti-A nor anti-B antibodies, making it safe for any patient. AB-negative plasma donors are in extremely high demand because they are so rare. The Rh factor does not affect plasma compatibility. If you are AB-negative, plasma donation is arguably your most valuable donation - consider becoming a regular plasma donor (every 28 days).
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