Milk Classes: What are they and what’s the difference between them?

Milk classes are often included in market reports, but what does that mean?

Milk is categorized into grades and classes based on its intended use and quality standards. But what’s the difference, and why do they matter?

What is a Milk Grade?

Milk grades denote the quality of the milk product and its suitability for either consumption or use in manufactured products like butter and cheese. There are two primary grades of milk: A, B, and AA.

  • Grade A: The highest grade, suitable for direct consumption as fluid milk. It meets stringent health and sanitation standards. Grade A milk is the only type sold as fluid milk for direct consumption.
  • Grade B: Used for manufacturing products like cheese, butter, and dry milk powder. It does not meet the same quality standards as Grade A.
  • Grade AA: This applies specifically to milk used for butter production. While Grade B milk can also be used for butter production, Grade AA is the highest grade for butter based on flavor, quality, and texture.

What is a Milk Class? What’s the difference between milk Classes I-IV?

The Federal Milk Order System uses four classes to categorize milk based on its end use rather than quality. These classes are often included in dairy market reports, but what is the difference between each of the four classes?

CoBank dairy economist Corey Geiger shares an easy way to remember the difference between different classes of milk products:

  • Class I: “Class I is beverage milk, it’s what you drink,” Geiger says.
  • Class II: “Class II is all the soft products,” he explains. “Think: ice cream, yogurt. Cottage cheese would [also] be in there because it’s a softer cheese, and the creamers that you see in coffee.”
  • Class III: “Class III is the largest class of milk, and it includes cheese and whey,” Geiger explains. “I always tell people we think of a nursery rhyme, ‘Miss Tuffett sat on her muffin, eating her curds and whey.’ Curds and whey are all of Class III.”
  • Class IV: “Class IV is butter and dry milk powders. Dry milk powders and non-fat dry milk are a key export. We export the product throughout the countries around the world, so those are Class III and IV.”

Geiger says Class 4 saw a big jump last year. Butter production was also the highest it has been in 77 years.

Related Stories
Among many longstanding traditions at the FFA Convention & Expo is the National FFA Band.
Trade pacts with Malaysia and Cambodia unlock tariff-free and preferential lanes for key U.S. farm goods, expanding long-term demand in Southeast Asia.
Alan Bjerga, Senior Vice President of Communications with the National Milk Producers Federation (NMPF), shares updates and resources available to dairy producers.
As we continue our Countdown to Convention presented by Culver’s, we meet some of the people who help bring the event to life.
A fast-moving series of trade signals from the White House and key partners is resetting the near-term outlook for U.S. agriculture.
Margin Protection and the new MCO add county-level margin tools — with earlier price discovery, input cost triggers, and high subsidy rates — to complement on-farm risk plans for 2026.

LATEST STORIES BY THIS AUTHOR:

Wayne Cockrell with the Texas and Southwestern Cattle Raisers Association joined us to discuss preparedness, producer awareness, and the industry’s response to New World screwworm concerns.
President Donald Trump speaks at the World Economic Forum in Davos, addressing SNAP spending, tariff threats against Europe, market reactions, and the upcoming USMCA review.
From meatpacking settlements to landmark NEPA rulings, Roger McEowen outlines the top legal developments in 2025 that will shape agriculture in the years ahead.
Alan Bjerga with the National Milk Producers Federation joined us to review new policies and regulations supporting the dairy industry and what they mean for the year ahead.
Despite rising costs and growing food insecurity, meat demand remained strong in 2025 as higher-income consumers offset cutbacks elsewhere. Economists break down the K-shaped economy, upcoming USDA cattle reports, livestock production outlooks, and renewed debate over beef imports and country-of-origin labeling heading into 2026.
Corn growers are turning to ethanol, E15 expansion, and export markets to help absorb record supplies and stabilize prices. Farm leaders discuss low-carbon ethanol demand, flex-fuel vehicle challenges, input costs, and the role of USMCA as producers look for market relief in the year ahead.
Agriculture Shows
Hosted by Scott “The Cow Guy” Shellady and RFD News Markets Specialist Tony St. James, Commodity Talk delivers expert insight into the day’s ag commodity markets just before the CME opens. Only on RFD-TV and Rural Radio SiriusXM Channel 147.
A look at the news, weather and commodities headlines that drove agriculture markets in the past week.
Everything profits from prairie. Soil, air, water — and all kinds of life! Learn how you can improve your land with prairie restoration, cover crops and prairie strips, while growing your bottom line.
Special 3-part series tells the story of the Claas family’s legacy, which changed agriculture forever.