No, A− red cells cannot be given to B+ patients. The ABO/Rh rules block it, and the crossmatch would reject the unit anyway. ## Why not B+ patients’s plasma carries antibodies that would attack A− red cells. A mismatched unit clumps inside the patient, the exact danger compatibility rules exist to prevent. ## What B+ patients CAN receive B+ patients can receive red cells from: O−, O+, B−, B+. ## What A− donors can do instead Your red cells still help: A−, A+, AB−, AB+, that is real, needed work. Register and let a compatible patient near you find you when the call comes. Plasma rules also run opposite to red cells (explained here).
Compatibility
Can A− donate blood to B+?
No, A− red cells cannot go to B+ patients. Which groups B+ can receive from, and what A− donors can do instead.
People also ask
Can A− donate blood to B+?
No, B+ patients can only receive from O−, O+, B−, B+.
Is A− to B+ safe in emergencies?
No, emergencies make compatibility matter more, not less; unknown-group patients get O−.
Where is this decided?
The blood bank crossmatch (see the crossmatch guide), never self-matched at home.
About this article
Written by Assam Blood Donor team. Medical review: pending, content follows published national (NBTC/NACO) guidance and is for general education, not personal medical advice. Last updated 11 Sept 2026.
Sources: NBTC donor selection criteria · standard donation-centre practice
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Reading is step one. Registering is step two.
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