What are the largest ethnic groups among immigrants today in the US?

There are no where near only three.

If you mean the three largest, they are:

# German-Americans # Afro-Americans # Irish-Americans If you wanted the larger super-ethnic groupings, here they are.

White American

Includes Americans of European, Middle Eastern and North African descent (such as Arab Americans, German Americans, English Americans and Italian Americans).

Black/African American

Includes anyone of Black African (Sub-Saharan) descent. Some groups in this category are: Afro-Americans whose ancestors came during the slavery period as West African slaves (there's no Word to distinguish this group and other African American groups, but it's there), Afro-Jamaican Americans, Afro-Hispanic Americans, Afro-Haitian Americans and Kenyan Americans.

Asian American

Asians are the various peoples of Asia, except for Middle Easterners, who are classified under "White" due to their fair skin regardless of continental origin. This group includes Chinese Americans, Japanese Americans, Korean Americans, Indian Americans, Pakistani Americans, Thai Americans and Lao Americans.

Native Americans

Native Americans are the descendants of the original ethnic groups present in the region before British (and French, Russian and Spanish) colonization. This group includes Athabaskans, Plains Indians, California tribes and Great Basin tribes. There are also many groups within this larger cultural groupings.

Native Hawaiian or other Pacific Islander

This group includes the Hawaiian people (also known as "Native Hawaiians"), their Polynesian cousins (Samoans, Fijians, etc.) and all of the peoples of the Pacific.

The largest are White, then Black, then Asian.