What is OU Kosher?
Also spelled / known as: Orthodox Union, OU certification, O-U symbol, Union of Orthodox
In brief
OU Kosher is the certification from the Orthodox Union — the largest kosher certifying agency in the world, supervising over 1,000,000 products from 10,000+ companies in 100+ countries.
OU Kosher explained
OU Kosher, also known as the Orthodox Union kosher certification, is administered by the Union of Orthodox Jewish Congregations of America. Founded in 1923, it is considered the gold standard of kosher certification worldwide. The distinctive circle-U symbol on a product indicates that it has been certified kosher by the OU's network of rabbis, mashgichim, and food scientists.
Real-world examples
A circle with the letter 'U' inside on a packaged food product
Restaurant storefront displaying 'Under OU Supervision'
Most major US kosher restaurants in Midtown Manhattan carry OU certification
Products like Oreos, Cheerios, and Coca-Cola are OU-certified
Context & nuance
The OU certifies meat (OU Meat), dairy (OU Dairy), and pareve products, along with full-service restaurants and food manufacturers. OU-D indicates a dairy product; OU-M or OU-Meat indicates a meat product; OU alone typically means pareve. For Passover, look for 'OU-P' which means OU certified for Passover. The OU maintains strict standards and is accepted universally in Orthodox communities.
Frequently asked questions
- What does OU Kosher mean?
- OU Kosher means a product or establishment has been certified kosher by the Orthodox Union, the largest and most widely recognized kosher certification agency in the world. The symbol is a circled letter U.
- Is OU Kosher reliable?
- Yes. OU Kosher is considered the most widely accepted kosher certification globally. It is recognized by virtually all Orthodox Jewish communities and is known for its rigorous standards and extensive rabbinic oversight.
- What's the difference between OU, OU-D, and OU-P?
- OU alone typically indicates a pareve product (neither meat nor dairy). OU-D means dairy. OU-M means meat. OU-P means certified kosher for Passover. Some products carry OU-DE, meaning dairy equipment was used but the product itself contains no dairy ingredients.
- How many products does OU Kosher certify?
- The Orthodox Union certifies over 1 million products from more than 10,000 companies in over 100 countries, making it by far the largest kosher certification agency in the world.
Cities where OU Kosher matters most
Find verified kosher listings in these communities where ou kosher is especially relevant.
Where OU Kosher shows up
These business categories are where you'll encounter ou kosher most often.
Related terms
Hechsher
A hechsher is the symbol printed on a kosher product or displayed by a kosher establishment indicating which rabbinic agency has certified it as meeting kosher standards.
Kashrut
Kashrut is the body of Jewish dietary law derived from the Torah, defining which foods are permitted (kosher) and forbidden (treif), how animals must be slaughtered, and how meat and dairy must be kept separate.
OK Kosher
OK Kosher Certification is one of the 'Big Four' kosher certifying agencies in the United States, founded in 1935 and known for its global reach across 100+ countries.
Star-K
Star-K Kosher Certification is a major international kosher agency based in Baltimore, Maryland, known for rigorous standards, extensive rabbinic supervision, and pioneering work on Shabbat-compliant appliances.
Pareve
Pareve (also spelled parve) refers to kosher foods that are neither meat nor dairy — fish, eggs, fruits, vegetables, grains, and most beverages — and can be eaten with either meat or dairy meals.
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