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Blood Donation Compatibility Chart: Who Can Give to Whom?

Updated 2026-11-07T00:00:00.000Z

Unlike personality charts, blood compatibility is real science, and getting it wrong can be dangerous. Hospitals always test and cross-match blood before a transfusion. This chart explains the basic rules.

Red blood cell compatibility

Your type Can receive red cells from Can give red cells to
O− O− Everyone
O+ O+, O− O+, A+, B+, AB+
A− A−, O− A−, A+, AB−, AB+
A+ A+, A−, O+, O− A+, AB+
B− B−, O− B−, B+, AB−, AB+
B+ B+, B−, O+, O− B+, AB+
AB− AB−, A−, B−, O− AB−, AB+
AB+ Everyone AB+

Why it works this way

Your red blood cells carry markers called antigens: A, B, both or neither (O). Your plasma carries antibodies against the antigens you don’t have. A type A person has anti-B antibodies, so type B red cells would be attacked.

Plasma is the other way round

Plasma carries the antibodies, so the rules flip:

Your type Can give plasma to
O O only
A A, O
B B, O
AB Everyone (universal plasma donor)

Should you donate?

Blood services almost always need O− and rarer types. Eligibility rules (age, weight, travel, health) differ by country, so check your national blood service. Donating is also the easiest way to find out your own blood type.

This page is general information, not medical advice.

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