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What is the rarest blood type?

AB negative: about 0.6% of people in U.S. reference estimates, or 1 in 167. All eight main types are ranked below, with two more references beside them.

Rarest

AB negative

0.6% · about 1 in 167

U.S. reference estimates

Next rarest

B negative

1.5% · about 1 in 67

U.S. reference estimates

Most common

O positive

37.4% · about 1 in 3

U.S. reference estimates

The eight main ABO and RhD types

All eight blood types, rarest first

U.S. reference estimates, with Australia and NHS donors beside them. Red-cell matching follows the Lifeblood table.

  1. #8AB negativeRarest0.6%about 1 in 167
  2. #7B negativeRarest1.5%about 1 in 67
  3. #6AB positive3.4%about 1 in 29
  4. #5A negative6.3%about 1 in 16
  5. #4O negative6.6%about 1 in 15
  6. #3B positive8.5%about 1 in 12
  7. #2A positive35.7%about 1 in 3
  8. #1O positive37.4%about 1 in 3

Three references, rarest U.S. type first. Rank #1 is the most common in each reference.

Blood typeU.S. referenceAustraliaNHS donorsCan receive red cells fromCan give red cells to
AB−0.6%1%1%AB−, A−, B−, O−AB+, AB−
B−1.5%2%3%B−, O−B+, B−, AB+, AB−
AB+3.4%4%2%AB+, AB−, A+, A−, B+, B−, O+, O−AB+
A−6.3%6%8%A−, O−A+, A−, AB+, AB−
O−6.6%7%14%O−O+, O−, A+, A−, B+, B−, AB+, AB−
B+8.5%12%8%B+, B−, O+, O−B+, AB+
A+35.7%32%28%A+, A−, O+, O−A+, AB+
O+37.4%38%36%O−, O+O+, A+, B+, AB+

Stanford Blood Center · AABB Technical Manual, 18th edition (Reference estimates; data year not stated); Australian Red Cross Lifeblood (2019 patient pathology results); NHS Blood Donation (February 2026). Australian shares are rounded as published and total 102%; NHS figures describe donors, not the UK population. Red-cell compatibility only: plasma and platelets follow different rules, and real transfusions need testing.

All three references · CSV Check your own blood type

The rarest blood type

AB negative is the rarest of the eight main blood types: about 0.6% of people in U.S. reference estimates, or 1 in 167. B negative follows at 1.5%, then AB positive at 3.4%. About 85% of people in these estimates are RhD positive, so each negative type is rarer than its positive twin.

The ranking is the same at the rare end in the other two references: AB negative is about 1% in Australian estimates and among NHS donors. Choose your own type in the blood type tool to see its share, its rank and a card you can share.

The most common blood type

O positive is the most common: 37.4% in U.S. estimates, 38% in Australia and 36% of NHS donors. A positive is close behind at 35.7% in U.S. estimates. B positive (8.5%) and O negative (6.6%) come next.

Rarer than any main type: golden blood

The eight types above describe two antigen systems, ABO and RhD. Red cells carry many other antigens, and some combinations are much rarer. The best known is Rh-null, nicknamed “golden blood”: red cells that lack every Rh antigen. A 2018 report in the International Journal of Hematology-Oncology and Stem Cell Research puts it at about 1 in 6 million people. It is not one of the eight types in these references, so it has no row in the chart.

Why O negative matters

In the Lifeblood red-cell matching table, O negative red cells can go to patients of all eight types, and AB positive patients can receive red cells from all eight. That is why O negative is in high demand even though 6.6% of people have it, and why 14% of NHS donors are O negative, more than twice its U.S. share. Plasma and platelets follow different rules; see the compatibility chart for red cells and real transfusions need testing.

How the three references differ

The U.S. figures are general reference estimates from Stanford Blood Center and the AABB Technical Manual; the source gives no survey year or sample size. The Australian figures come from Lifeblood’s 2019 patient pathology results and are rounded to whole percentages that total 102%. The NHS figures, dated February 2026, describe donors, not the UK population. Each is kept as published and never averaged; the methodology has the detail.

Good questions

What is the rarest blood type?

AB negative, at about 0.6% of people in U.S. reference estimates, or 1 in 167. B negative is next at 1.5%. AB negative is also the rarest of the eight main types in Australian estimates and among NHS donors, at about 1%.

What is the most common blood type?

O positive: 37.4% of people in U.S. reference estimates, just ahead of A positive at 35.7%. Together they cover almost three in four people.

What is golden blood?

“Golden blood” is a nickname for Rh-null, red cells that lack every Rh antigen. It is far rarer than any of the eight main types: about 1 in 6 million people, according to a 2018 case report in the International Journal of Hematology-Oncology and Stem Cell Research.

What is the rarest blood type in the world?

Among the eight main ABO and RhD types, AB negative is the rarest in each reference here. Rarer blood types exist beyond those eight; Rh-null is the best known, at about 1 in 6 million people. No single survey measures blood types for the whole world.

How rare is O negative blood?

About 6.6% of people in U.S. reference estimates, 1 in 15. O negative red cells can be given to patients of any ABO and RhD type in the Lifeblood matching table, which is why O negative donors are asked to give often; 14% of NHS donors are O negative.

How rare is AB negative blood?

About 0.6% of people in U.S. reference estimates, 1 in 167, and about 1% in Australian estimates and among NHS donors.

How rare is O positive blood?

It is the most common type: 37.4% in U.S. estimates, 38% in Australia and 36% of NHS donors.