Microlot and micromill show up constantly on specialty coffee bags, look nearly identical, and mean different things.
- Microlot tells you what stayed separate. A small quantity of coffee kept traceable to one farm, one section of a farm, one group of trees, one picking, or one processing method, never blended into anything larger.
- Micromill tells you who did the processing. A producer milling their own cherry, on their own land, with equipment they own.
A bag carrying both means the person who grew the coffee also processed it, and kept a portion of their best work separate.
Neither term guarantees the coffee tastes good. More on that below.
Why Both Terms Exist
Most coffee producers don't sell beans. They grow and harvest coffee cherry and sell it to a mill, which weighs it and pays by the pound. Everyone in the area usually has the same arrangement with the same regional mill, so cherry from dozens or hundreds of farms gets combined and processed together.
Consider what that does to quality. A producer who waits for full ripeness and picks only the reddest cherry earns the same rate as a neighbor who strips whole branches and goes home early. The mill isn't measuring quality. It's measuring weight.
In fairness, at that moment the mill can't measure much else. Quality at the farm gate gets judged by eye. Is the cherry ripe and evenly red, is there insect damage, is anything rotting or overripe. Those markers are real and they matter, but they aren't cup quality.
Finding out how a coffee actually tastes takes the whole sequence: process it, dry it for a week or two, hull it, roast a sample, and put it in front of a certified taster working through a formal cupping protocol. All of that happens weeks after the cherry changed hands and long after it was mixed with everyone else's. The information shows up too late for the transaction to use it.
That timing shapes everything downstream. Without a way to prove quality at the point of sale, there's no premium to earn, and without a premium, there's little reason for a producer to take on processing.
Why Producers Sell Cherry Instead of Beans
Coffee cherry is perishable fruit, and the clock starts the moment it leaves the tree. Within roughly 8 to 24 hours it has to be depulped or spread out to dry, or it begins to rot and the harvest is lost.
Meeting that deadline takes equipment and space. A depulper to strip the skin. Fermentation tanks. Water in real volume, plus somewhere for the wastewater to go. Drying beds or patios that stay occupied for one to two weeks per batch and need turning by hand. For someone farming a couple of hectares, that's a serious investment for a crop that comes in once a year.
Payment timing matters too. Cherry delivered to the mill this afternoon is money this afternoon. Processing your own coffee means waiting weeks for it to dry, then finding a buyer, then waiting again. Selling cherry is the arrangement that keeps a small farm solvent.
Who Decides What Becomes a Lot
A lot is coffee that is grouped together and gets sold as one unit. The size isn't fixed. It can be a full shipping container, roughly 37,500 pounds, or a handful of bags.
Lots get drawn at the mill, during and after processing, and whoever runs the equipment makes the call. They decide what stays separate and what goes into the larger pile. Coffee can be divided by farm, by altitude, by a group of trees, by a single day's picking, or by processing method, and every one of those choices belongs to the mill.
That single fact explains both words.
Microlots Came From Buyers
Starting in the 1990s, importers went looking for exceptional coffee that was vanishing into commodity blends. They asked for it to be kept separate and paid a premium to get it.
The buyers driving this were often small importers who traveled to origin, cupped their way across member farms of a cooperative, and kept finding remarkable coffees grown by people earning no more than anyone else. Asking for those coffees by name, and paying more for them, was the only way to change that math.
Separation also solves the timing problem. A cup score arrives weeks or months after harvest, long after pooled cherry has lost any connection to who grew it. A lot that stayed separate still carries a name, so an importer holding to a high standard can pay a premium back to the specific producer whose coffee earned it, well after the fruit came off the tree.
That closes a feedback loop which stayed open through most of coffee's history. A producer learns that the extra passes through the rows, the patience to wait for full ripeness, the longer drying time, showed up in the cup and showed up in the payment. Next harvest they know exactly what to repeat. Quality turns into something a producer can invest in and expect a return on, which is the condition under which anything gets better year over year.
Micromills Came From Producers
A producer hauling cherry to the community mill has almost no say in whether their best picking gets evaluated on its own. Somebody else owns the depulper, so somebody else decides.
Around 2000, Costa Rican producers started changing that. They took small bank loans, bought their own depulpers, and built their own drying beds. Costa Rica went from one independent mill to more than 150 in about a decade, and new ones open every year.
Owning the equipment means owning the decisions: how long to ferment, how long to dry, how much fruit to leave clinging to the bean, and which coffee gets separated and sold on its own. The honey and natural processed coffees that specialty roasters build menus around came largely from producers who could finally experiment with their own harvest.
Microlots came first by roughly a decade. An estate with its own wet mill could always section off its best plot. A smallholder with two hectares and a truck could not, because their coffee joined everyone else's the moment it left their hands. The micromill is how small producers got to make microlots of their own.
Neither Term Guarantees Quality
No certifying body governs either word. There's no minimum cup score and no enforcement.
A coffee can be called a microlot for the sole reason that it was never mixed with anything else, which is a bookkeeping fact and says nothing about flavor. Anyone along the chain can apply the label. Some microlots are extraordinary. Others are ordinary coffee that happened to stay in its own bag.
Certifications work the same way. Shade grown, bird friendly, rainforest certified, and the rest describe real practices that many people care about, our team included. None of them can make a poorly grown or badly processed coffee taste good.
What Actually Predicts a Good Cup
Cup score. Trained tasters evaluate coffee on a 100-point scale. Specialty grade starts at 80, which already puts a coffee in the top few percent worldwide. Above 87 is rare.
Whether somebody tasted it before buying it. Cupping samples before purchase is a quality decision. Buying from a written description is a purchasing decision. At I Have a Bean, our head roaster oversees the roasting of a dozen or more 50-gram samples most weeks. Our team evaluates every one, and roughly 95% get rejected. A label can't make bad coffee taste good.
Roast date. The finest microlot in the world tastes flat four months after roasting. Roast date does more for your morning cup than any sourcing term, which is why we roast to order instead of roasting to inventory. Our guide on how to keep coffee fresh covers what happens once the beans reach you.
Read microlot and micromill as background about where a coffee came from and who handled it. That's real information, and it usually signals a supply chain where somebody was paying attention. It just isn't a verdict.
Common Questions
How big is a microlot?
There's no fixed size. Microlots range from a few bags to a few dozen. Separation and traceability define the term, not weight.
Is a microlot the same as single origin?
No. Single origin can be as broad as a country or region. A microlot is far more specific. Every microlot is single origin, and most single origin coffee is not a microlot.
Why did micromills start in Costa Rica?
Falling commodity prices through the 1990s made it harder to earn a living selling cherry by weight. Beginning around 2000, producers bought their own processing equipment so they could control quality and negotiate on their own terms.
Does the premium on a microlot reach the producer?
That's the intent behind the model, and traceability is what allows a specific producer to be identified and paid. The outcome depends on the importer and the roaster, so it's fair to ask a roaster how they source.
Browse our current lineup at ihaveabean.com. Every coffee we sell was tasted before we bought it, roasted to order, and shipped the same day, backed by our No-Risk, No-Hassle, Gonna Love It Guarantee.