O negative, A negative, B negative, AB negative — the groups banks always run short of, and why registers matter.
In India, negative blood groups are rare: O− is well under 1 in 30 people; AB− about 1 in 250. That makes negative patients the hardest to serve in an emergency — and negative donors the most valuable people on any register.
O− is the universal red-cell donor: every patient can receive O− in a crisis. When a bank says “we have nothing left”, it usually means O−.
If your group is negative:
- You may be the only match a negative patient in your district has.
- Consider registering even if you donate rarely — emergency pings are infrequent and you can always decline.
- Learn your group if you don’t know it: free at any camp.
Explore your group: O− · A− · B− · AB−
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 26 Aug 2026.
Sources: National Blood Transfusion Council (NBTC) guidance · NACO Voluntary Blood Donation Programme · Assam SBTC donor criteria
Reading is step one. Registering is step two.
Two minutes, phone OTP, no passwords. We contact you only when a patient near you needs your group.
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