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Kosher Catering

Hechsher Decoder: OU vs Star-K vs Kof-K vs OK (and Why It Matters for Your Caterer)

The Mitzvah GuideMay 3, 20269 min read
Hechsher Decoder: OU vs Star-K vs Kof-K vs OK (and Why It Matters for Your Caterer)

If you've started shopping for a kosher caterer, you've already noticed: every caterer claims to be kosher, but the symbols on their materials are different, and their answers about supervision are vague in ways that should make you pause.

This is a real problem. Kosher is not a vibe — it's a structured certification system, and the level of trust you can place in any caterer's claim depends entirely on who is supervising them and how. Here's the honest decoder.

The big four hechshers (and what they actually mean)

The major US kosher certifying bodies — the ones whose stamps you see on packaged food and on caterer materials — are OU, Star-K, Kof-K, and OK Kosher. There are dozens of others (CRC, KVH, KSA, OK², regional Vaads), but if you're in the NY/NJ/Boca/LA/Chicago/Boston market, you'll mostly see those four.

OU (Orthodox Union)

The oldest and largest. Star-shaped U logo. Universally accepted across all Orthodox communities (Modern Orthodox through Yeshivish). If a vendor has reliable OU certification, every guest who keeps kosher will eat. Their published list is searchable at oukosher.org.

Star-K

Based in Baltimore, particularly strong in the Mid-Atlantic and DC area. Accepted broadly. Some communities consider Star-K's standards slightly more stringent than OU on certain edge cases (e.g. dairy supervision). Searchable at star-k.org.

Kof-K

Strong in the NY/NJ region, especially Bergen County and Teaneck. Universally accepted. Highly visible in the bar/bat mitzvah catering circuit. List at kof-k.org.

OK Kosher

Brooklyn-based, particularly common in Chabad and Lubavitch settings. Accepted across most Orthodox communities. List at ok.org.

Key principle: If a vendor claims any of these four hechshers, you can verify the claim by searching the certifier's published list. If their name isn't on the list, the claim is false. We do this for every kosher caterer on The Mitzvah Guide.

What hechsher does NOT tell you

Here's where things get nuanced. Knowing a caterer is OU-certified at their facility tells you that food prepared in their kitchen is kosher. But you're hiring them to cater an event at a venue, and that's a different question.

Three things to verify beyond the basic certification:

1. Off-premise supervision

Will a mashgiach (kosher supervisor) be physically present at your event venue, before and during service? At what times? For how long? Reputable kosher caterers include this as standard; budget caterers cut corners here.

2. Cholov yisroel

Some Orthodox communities require dairy supervised under a specific standard called cholov yisroel — meaning a Jewish supervisor was present from milking onward. This matters for dessert, dairy entrées, and cheeses. Ask: "Is your dairy cholov yisroel?" If your guest list includes Yeshivish or Lubavitch families, this matters.

3. Pas yisroel and bishul yisroel

Pas yisroel is bread baked or kindled by a Jew. Bishul yisroel is cooked food where a Jew was involved in the cooking. Stricter communities require both. Most NY/NJ-area mitzvah caterers handle both as standard, but not all do.

Glatt vs kosher vs kosher-style

These three terms are often used interchangeably online. They are not the same thing.

Glatt kosher

Originally a meat-specific term meaning the animal's lungs were smooth (no adhesions). In modern usage, "glatt kosher" loosely means strictest level of meat kashrut — and is often used as a general signal that the establishment maintains high standards across the board (utensils, equipment, supervision). All four major hechshers above can certify glatt.

Kosher (kosher-supervised)

Certified kosher under a recognized hechsher. The caterer has a mashgiach. Kitchen is exclusively kosher (or properly separated meat/dairy). Most Orthodox guests will eat. Conservative guests almost always will.

Kosher-style

Not kosher. This means the caterer cooks "in the spirit of" kosher — no shellfish, no pork, no obvious meat-and-dairy combos — but the kitchen isn't supervised, equipment isn't separated, and ingredients aren't kashrut-checked. Kosher-keeping guests will not eat kosher-style food.

If you're hosting any guests who keep kosher and your caterer is kosher-style, you have a real problem. Either solve it (separate fully-sealed kosher meal trays delivered in from a real kosher caterer) or change caterers. There is no middle ground here.

Where caterers fudge

Common patterns we've seen on caterer websites and in initial conversations:

Always ask: "Which certifying body provides your hechsher, and may I have a link to your listing on their published vendor list?" A real kosher caterer answers this in 30 seconds. A fake one stalls.

The Mitzvah Guide hechsher policy

Every kosher caterer listing on this site carries one of these tags, and we never let a vendor self-attest:

We link the certifying body's listing on every kosher caterer page. If the link breaks, we re-verify within 14 days.

Questions to ask any kosher caterer before signing

Print these and bring them to your meeting:

  1. Which certifying body provides your hechsher? Can you send me your listing on their site?
  2. Will a mashgiach be physically present at our venue? When does coverage start and end?
  3. Is your dairy cholov yisroel? Is your bread pas yisroel?
  4. Can you handle multiple kashrut levels at the event (e.g., glatt for some guests, regular for others)?
  5. How do you handle the kitchen at our venue if it's not normally kosher? Do you self-cater entirely, or use the venue kitchen with kashering protocols?
  6. What's your protocol for Shomer Shabbat staff if our event runs past sundown Saturday into Sunday?
  7. Can I see references from three recent mitzvahs you catered?

The right caterer answers each of these in writing. The wrong one says "trust us."

When in doubt: ask a rabbi

Every Orthodox synagogue and every Conservative synagogue with a USY-active rabbi can advise on kashrut for your specific guest list. They'll tell you which hechshers are accepted by your community and what compromises (if any) are reasonable. This call costs you nothing and resolves the question definitively.

Next steps

We update this guide whenever the major certifying bodies change their published standards. Last updated: May 2026.