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Blood Type by Country: Where Each Type Is Most Common

Where O, A, B and AB blood are most common, with country percentages and where Rh-negative blood is common and where it almost never shows up.

By Written Facts Staff7 min read

Type O is the most common blood type in most of the world. It peaks in Latin America, where Ecuador and Peru report more than 70% of people as O. Type A leads in parts of Europe, such as Norway and Armenia. Type B is most common in South Asia: India, Pakistan and Bangladesh all report about a third of people as B. AB is rare everywhere, but it is most common in Korea, Japan and China. Rh-negative blood is most common in Western Europe, and its highest known rate is among the Basque people. In China, Korea and Japan it almost never shows up.

The country figures below come from the national surveys collected in Wikipedia's blood type distribution by country table. Each country's numbers come from a different blood bank or study, with different sample sizes, so treat them as close estimates and don't compare small differences. The regional patterns are well established. The decimals are less certain.

Type O: Latin America and Indigenous peoples

Figures for O include both O-positive and O-negative.

  • Ecuador: about 77%
  • Peru: about 71%
  • Colombia: about 66%
  • Mexico: about 62%
  • Nigeria: about 53%
  • Saudi Arabia: about 52%
  • United States: about 44%

The Latin American numbers are high because of Indigenous ancestry. Researchers who study the ABO gene note that many Native American populations are close to 100% type O, which isn't seen anywhere else. A 2013 study in the American Journal of Physical Anthropology followed one variant of the O gene that is shared among Native American groups and rare elsewhere. It supports the idea that the variant arose in Beringia, the old land bridge between Asia and Alaska, before people spread through the Americas.

You can see the same pattern in the U.S. The American Red Cross puts O-positive at about 53% of Latino Americans, compared with about 37% of white Americans, according to Medical News Today's summary of Red Cross data.

Type A: Northern and Central Europe, Armenia, Japan

Type A is the second most common type in the world. In several countries it moves into first place.

  • Armenia: about 50%
  • Norway: about 49%
  • France: about 45%
  • Austria: about 44%
  • Sweden and Denmark: about 44%
  • Japan: about 40%

Type A is also common in the U.S. (about 42% counting A-negative), which is about level with type O at 44%. That's why blood banks there always want both.

Type B: South Asia and China

In most of Europe and the Americas, type B sits under 12%. Move east and it climbs fast.

  • India: about 34%
  • Bangladesh: about 34%
  • Pakistan: about 33%
  • China: about 29%
  • South Korea: about 27%
  • Japan: about 20%

In Bangladesh, B-positive is reported as the single most common type, ahead of O-positive. India and Pakistan are close to a tie between B and O. For comparison, Peru reports about 8% type B and Ecuador about 7%.

Type AB: East Asia

AB is the rarest of the four ABO groups almost everywhere. Its highest numbers are in East Asia.

  • South Korea: about 11.5%
  • Japan: about 10%
  • Bangladesh: about 10%
  • Pakistan: about 10%
  • China: about 8.5%

In the U.S. it's about 4%. In Ecuador it's about 0.5%. If you want the full ranking of all eight types, see blood types ranked from most common to rarest.

Rh-negative: Europe high, East Asia almost none

The plus or minus in your blood type is the Rh factor, also called RhD. It varies by region even more than A, B and O do. We cover what it means and why it matters in pregnancy on our Rh-negative blood page.

Here's how Rh-negative rates vary by region:

  • Basque Country (Spain and France): highest known. A 2018 study in the European Journal of Human Genetics found Basques have the world's highest frequency of the gene deletion behind Rh-negative blood, at 47.2%. Keep in mind that 47.2% is how common the gene is, not the share of people who are Rh-negative. You need two copies to be Rh-negative, so the share of Basque people who test negative is lower. The figure most often given is around a quarter to a third.
  • Europe in general: up to about 17%, per a 2021 review in the Journal of Translational Medicine. The country surveys put the UK at about 20%, Spain about 18.5%, Ireland about 16% and Norway about 15%.
  • United States: about 14% in the same review. U.S. blood bank figures put it at about 15%.
  • Africa: typically about 10% in that review's numbers. The country surveys run lower in some places, such as about 5% in Nigeria.
  • India: about 6% in the survey figures.
  • Latin America: low. About 2% in Peru, 3 to 4% in Ecuador and about 4% in Mexico, again because of Indigenous ancestry.
  • China, Korea and Japan: the lowest in the world. Among Han Chinese, reported rates run from 0.24% to 0.50%. In China, the Uyghur people have the highest reported rate, at 3.3 to 4.7%.

East Asia has one more twist. The same 2021 review found that about 23% of Han Chinese who test Rh-negative actually have a weak form of the D antigen called DEL. Standard tests miss it, but it can change how doctors handle transfusions and pregnancy.

In practice, a hospital in Seoul or Shanghai has very few Rh-negative donors. An Rh-negative traveler who needs blood there may depend on a small registry of local donors. In the UK, about one person in five shares that blood type.

Why blood types cluster by region

Nobody has a full answer, and you should be skeptical of anyone who says they do. The leading explanations fall into three groups:

  • Founder effects and genetic drift. A small group settles a new region, and whatever blood types it happened to carry become the local norm. This fits the Americas well.
  • Isolation. Populations that mixed less with their neighbors, like the Basques, kept unusual frequencies longer.
  • Disease pressure. Scientists have long suspected that some types gave an advantage against certain infections. The Basque study notes that both the demographic and the adaptive explanations have been suggested, and that neither has been clearly shown.

You'll also see claims online that Rh-negative people descend from a separate ancient group, or something stranger. The genetics doesn't support that. Rh-negative is a common gene deletion, and it turns up all over the world at different rates.

What this means for you

  • Your ancestry is a good guess at your blood type, nothing more. Plenty of people of Korean ancestry are type O, and plenty of Peruvians are type A. Get tested if you need to know.
  • If you're Rh-negative and pregnant, ask your doctor about Rh immune globulin, wherever you live.
  • If you're a rare type for where you live, such as Rh-negative in East Asia or AB anywhere, your donation counts for more. Ask your local blood service whether they keep a rare-donor list.
  • Want to see something truly rare? Read about golden blood, Rh-null. Fewer than 50 people are known to have it.

Related: Can Two Parents Have a Child With a Different Blood Type?

Sources (5)

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