Blood Type Compatibility Chart
Who can donate to whom?
Review general ABO and Rh compatibility for red blood cell and plasma transfusions.
| Recipient | ||||||||
|---|---|---|---|---|---|---|---|---|
| Donor | O− | O+ | A− | A+ | B− | B+ | AB− | AB+ |
| O negative donor to O negative recipient: compatible | O negative donor to O positive recipient: compatible | O negative donor to A negative recipient: compatible | O negative donor to A positive recipient: compatible | O negative donor to B negative recipient: compatible | O negative donor to B positive recipient: compatible | O negative donor to AB negative recipient: compatible | O negative donor to AB positive recipient: compatible | |
| O positive donor to O negative recipient: not compatible | O positive donor to O positive recipient: compatible | O positive donor to A negative recipient: not compatible | O positive donor to A positive recipient: compatible | O positive donor to B negative recipient: not compatible | O positive donor to B positive recipient: compatible | O positive donor to AB negative recipient: not compatible | O positive donor to AB positive recipient: compatible | |
| A negative donor to O negative recipient: not compatible | A negative donor to O positive recipient: not compatible | A negative donor to A negative recipient: compatible | A negative donor to A positive recipient: compatible | A negative donor to B negative recipient: not compatible | A negative donor to B positive recipient: not compatible | A negative donor to AB negative recipient: compatible | A negative donor to AB positive recipient: compatible | |
| A positive donor to O negative recipient: not compatible | A positive donor to O positive recipient: not compatible | A positive donor to A negative recipient: not compatible | A positive donor to A positive recipient: compatible | A positive donor to B negative recipient: not compatible | A positive donor to B positive recipient: not compatible | A positive donor to AB negative recipient: not compatible | A positive donor to AB positive recipient: compatible | |
| B negative donor to O negative recipient: not compatible | B negative donor to O positive recipient: not compatible | B negative donor to A negative recipient: not compatible | B negative donor to A positive recipient: not compatible | B negative donor to B negative recipient: compatible | B negative donor to B positive recipient: compatible | B negative donor to AB negative recipient: compatible | B negative donor to AB positive recipient: compatible | |
| B positive donor to O negative recipient: not compatible | B positive donor to O positive recipient: not compatible | B positive donor to A negative recipient: not compatible | B positive donor to A positive recipient: not compatible | B positive donor to B negative recipient: not compatible | B positive donor to B positive recipient: compatible | B positive donor to AB negative recipient: not compatible | B positive donor to AB positive recipient: compatible | |
| AB negative donor to O negative recipient: not compatible | AB negative donor to O positive recipient: not compatible | AB negative donor to A negative recipient: not compatible | AB negative donor to A positive recipient: not compatible | AB negative donor to B negative recipient: not compatible | AB negative donor to B positive recipient: not compatible | AB negative donor to AB negative recipient: compatible | AB negative donor to AB positive recipient: compatible | |
| AB positive donor to O negative recipient: not compatible | AB positive donor to O positive recipient: not compatible | AB positive donor to A negative recipient: not compatible | AB positive donor to A positive recipient: not compatible | AB positive donor to B negative recipient: not compatible | AB positive donor to B positive recipient: not compatible | AB positive donor to AB negative recipient: not compatible | AB positive donor to AB positive recipient: compatible | |
Compatible: donor red blood cells can be transfused to recipient Not compatible
Universal red cell donorO negative
Universal red cell recipientAB positive
Transfusion decisions require compatibility testing by qualified medical professionals.
O− red cells can go to
- O−
- O+
- A−
- A+
- B−
- B+
- AB−
- AB+
O− can receive red cells from
- O−
O negative is the universal red cell donor.
Important: This chart shows general ABO and Rh compatibility for transfusions. It is provided for educational purposes only and is not a substitute for crossmatching or clinical judgment. Always rely on laboratory testing and the guidance of qualified healthcare professionals for transfusion decisions.
Frequently
Asked Questions
Why is O negative the universal red cell donor?
O negative red cells carry no A, B, or RhD antigens, so a recipient's antibodies have nothing to react against. That makes O− red cells usable for recipients of any ABO/Rh type in the simplified model, which is why they are stocked for emergencies.
Why is AB positive the universal red cell recipient?
AB positive people have A, B, and RhD antigens on their red cells and therefore no anti-A, anti-B, or (typically) anti-D antibodies. They can generally receive red cells from any ABO/Rh type.
What about Rh factor and compatibility?
Rh-negative recipients should generally receive Rh-negative red cells to avoid forming anti-D antibodies. Rh-positive recipients can receive either. Plasma compatibility does not depend on Rh in the same way.
Why is plasma compatibility the opposite of red cells?
Red cells carry antigens; plasma carries the antibodies against the antigens a person lacks. AB plasma has no anti-A or anti-B antibodies, so it can be given to anyone. Type O plasma contains both antibodies, so it is generally only given to type O recipients.
How compatibility works
Red blood cells display antigens: A, B, both, or neither, plus the RhD antigen if Rh-positive. Plasma contains antibodies against the ABO antigens a person does not have. If donor red cells carry an antigen the recipient has antibodies against, the recipient's immune system attacks the transfused cells.
For red cells, a donor is compatible when they introduce no new ABO antigen and, if the recipient is Rh-negative, no RhD antigen. For plasma, the logic flips: the donor's plasma must not contain antibodies against the recipient's red cells, so AB plasma (no anti-A or anti-B) is the universal plasma donor and type O is the universal plasma recipient.
Go deeper
Sources
Information on this page is paraphrased from the following authoritative sources.
- Facts About Blood and Blood Types(opens in a new tab)American Red Cross
- Blood typing(opens in a new tab)MedlinePlus, U.S. National Library of Medicine