Hemp COA: What It Is and How to Read One
Every batch of hemp flower we ship from our Wilmore, Kentucky farm gets sampled and sent to a third-party lab before it reaches a customer. The lab report that comes back is called a Certificate of Analysis, or hemp COA. It's the only document standing between marketing copy and what's actually inside the bag.
This post explains what a hemp COA is, what gets tested, how to read the results without a chemistry degree, and what red flags should make you walk away from a brand. We've been farming hemp in Wilmore, Kentucky since 2018, and our COAs are public for every product batch we ship, from CBD hemp flower to gummies to tinctures.
What Is a Hemp COA (Certificate of Analysis)?
A hemp COA is a lab report. An accredited third-party lab takes a sample from a specific batch of hemp flower, oil, gummies, or topicals, runs it through a panel of chemistry tests, and issues a dated document showing what they found. Cannabinoid percentages. Pesticide residues. Heavy metals. Microbial counts. Anything the test was set up to look for.
The COA covers one batch. Not the brand. Not the product line. The specific lot number on the bag in your hand. If the brand can't connect a COA to the batch you bought, the document doesn't actually mean anything for that purchase.
Why Every Hemp Product Needs a COA
Hemp is minimally regulated at the federal level. The 2018 Farm Bill legalized hemp under 0.3% Delta-9 THC, but it didn't set a national framework for purity testing, potency labeling, or contamination limits the way the FDA does for food and pharmaceuticals. State rules vary. Some states require COA-backed labels. Many don't.
A COA is the only way a buyer can verify what a hemp product actually contains. Without one, the cannabinoid percentage on the label is an unverified claim. So is the pesticide-free claim. So is the absence of heavy metals or mold. The COA is the receipt.
Who Performs Hemp Lab Testing?
Independent third-party labs. These are testing facilities with no ownership stake in the brands they test for. The credibility of a hemp COA depends on the lab being separate from the seller, and on the lab itself being accredited. The most common standard is ISO/IEC 17025, the international accreditation for testing and calibration laboratories.
In-house testing isn't the same. A brand testing its own product has a conflict of interest baked in. Look for the lab name on the COA, confirm it's a real independent lab, and check the accreditation if you want to be thorough.
What a Hemp COA Tests For
A complete hemp COA covers six panels. Not every product requires every panel. Hemp flower doesn't need solvent residue testing because no solvents were used to make it. Tinctures and extracts do, because they're produced with CO2 or ethanol extraction.
Cannabinoid Profile (CBD, THC, CBG, CBN Percentages)
This is the potency panel. The lab measures the concentration of each cannabinoid by weight, usually as a percentage and a milligram-per-gram value. CBD is the headline number for most hemp flower. CBG, CBN, CBC, THCa, and Delta-9 THC are listed alongside it.
Two numbers matter most for verification. The CBD percentage tells you whether the product matches what the label claims. The Delta-9 THC percentage has to come in under 0.3% by dry weight for the product to be Farm Bill compliant.
Pesticide and Herbicide Screening
The pesticide panel screens for dozens of agricultural chemicals. Glyphosate. Myclobutanil. Bifenthrin. Pyrethrins. The full list runs to 60-plus compounds depending on the lab. A clean panel shows ND (not detected) or a value below the regulatory action limit for every chemical tested.
Hemp is what's called a bioaccumulator. The plant pulls things out of the soil, including pesticides if they're present, and concentrates them in the flower. That's why the pesticide panel matters more for hemp than it does for many other agricultural products.
Heavy Metal Testing (Lead, Arsenic, Mercury, Cadmium)
Same bioaccumulator principle. Hemp pulls heavy metals out of soil. Lead, arsenic, mercury, and cadmium are the four standard targets. Each has an action limit measured in parts per million or parts per billion. A passing panel shows results below those limits or marked ND.
Microbial Safety Testing (Mold, Bacteria, Yeast)
The microbial panel checks for biological contamination. Aspergillus species (a mold), E. coli, Salmonella, total yeast and mold counts, and total aerobic bacteria. Hemp flower is dried plant material, and dried plant material can grow mold if it's stored wrong. The microbial panel catches that before product ships.
Solvent Residue Testing (for Extracts)
Only relevant for extracted products. Tinctures, distillates, vape cartridges, and concentrates are made with CO2, ethanol, or hydrocarbons. Residual solvents in the finished product are tested against safety thresholds. Hemp flower itself skips this panel.
Terpene Profile (Full-Spectrum Products)
Optional but useful. Terpenes are the aromatic compounds responsible for a strain's smell and flavor. Myrcene. Limonene. Pinene. Linalool. A full-spectrum hemp product will often include a terpene profile so buyers can see the strain's character on paper, not just on the label.
How to Read a Hemp COA Step by Step
Most COAs are two to four pages of dense lab data. Here's how to read one quickly.
Finding the Cannabinoid Potency Panel
The cannabinoid panel is usually on page one. It lists each cannabinoid (CBD, CBDA, Delta-9 THC, THCa, CBG, CBN, and so on), the result by weight, and a unit (% or mg/g). Compare the CBD result against what the label claims. They should match within a few percentage points.
Checking THC Compliance (<0.3% Delta-9 THC)
Find the Delta-9 THC row. Check that the value is below 0.3% on a dry weight basis. That's the federal Farm Bill threshold. Anything above it and the product isn't legally hemp. Note that THCa, the precursor cannabinoid, is reported separately and is not bound by the 0.3% limit at the federal level.
Understanding LOD, LOQ, and ND (Not Detected) Results
Three abbreviations show up over and over on COAs.
LOD is the Limit of Detection. It's the smallest amount of a compound the test can pick up at all.
LOQ is the Limit of Quantitation. It's the smallest amount the test can measure accurately. Below the LOQ, the lab can tell something is there but not exactly how much.
ND means Not Detected. A pesticide or heavy metal showing ND was below the LOD, which is the strictest result the test can return. ND is what you want to see on every contaminant panel.
Identifying the Testing Lab and Accreditation
The lab's name, address, and accreditation number are usually printed at the top or bottom of the report. Confirm the lab is not the same company as the seller. If the COA is signed and dated, check the date. A COA from two years ago doesn't tell you anything about the batch you just bought.
Wholesale Hemp Farms' Quality Assurance Process
Our quality assurance starts before the seed goes in the ground.
From Seed to Harvest: Where Testing Starts
We grow on certified organic soil in Wilmore, Kentucky. Our soil gets tested before each season. Our inputs are USDA-allowed organic inputs. The crop gets walked weekly during the grow. We pull samples from each flowering field and submit them for pre-harvest cannabinoid screening to confirm the Delta-9 THC level will come in compliant.
After harvest, every batch gets sampled and shipped to a third-party lab. Nothing leaves the farm until the COA is back and the panel reads clean.
USDA Organic Certification and What It Means for Testing
USDA Organic isn't a marketing label. It's a federal certification with annual third-party audits of our soil, our seed sources, our pest management, and our post-harvest handling. The certification rules out synthetic pesticides, synthetic fertilizers, sewage sludge, irradiation, and genetic engineering before any hemp ever gets to the lab. So the COA is testing what the certification has already filtered.
For the deeper version, see our explainer on organic CBD vs non-organic CBD and our USDA Organic certification page.
How to Find WHF's COAs
Every batch we ship has a public COA. They're indexed on our Third Party Labs page, organized by product. Hemp flower strains, CBD gummies, mushroom gummies, tinctures, and topicals each have their own COA links. If you bought a specific batch and want the matching COA, the lot number on your label maps to the file on that page.
If you have a question about something on a COA, reply to your order confirmation. You'll get a real farmer on this end.
Red Flags: What to Do If a Brand Can't Show You a COA
A few warning signs come up over and over with brands that aren't doing the testing they claim.
The COA isn't on the website at all. If a brand says it tests but won't show the report, the testing isn't happening at the level the marketing implies.
The COA is undated, or older than 12 months. Hemp batches change. A COA from a previous crop doesn't speak for what's on the shelf right now.
The lab on the COA is the same company as the brand. In-house testing isn't third-party testing.
The COA shows only the cannabinoid panel and no contaminant panels. Potency without purity is half the picture. You want pesticides, heavy metals, and microbials all on the same report.
The numbers on the COA don't match the label. A 1,000 mg tincture that tests at 600 mg has a labeling problem. A flower marketed as "high CBG" with 0.4% CBG on the COA has the same issue.
If any of these show up, walk away. There are plenty of brands publishing complete, current, third-party COAs. A brand that can't or won't isn't worth the gamble.
FAQs About Hemp COAs
What is a hemp COA? A Certificate of Analysis is a third-party lab document showing the test results for a specific batch of hemp product. It covers cannabinoid percentages, pesticide residues, heavy metals, microbial safety, and (for extracts) residual solvents.
Why do hemp products need a COA? Hemp is minimally regulated, and a COA is the only way a buyer can verify what's actually inside the bag. The label is a claim. The COA is the verification.
What should I look for in a hemp COA? A cannabinoid panel with CBD% close to the label and Delta-9 THC under 0.3%, pesticide and heavy metal panels showing ND or below action limits, a microbial panel showing pass, the name of an accredited third-party lab, and a recent date.
How do I know if a hemp COA is legitimate? Confirm the lab is ISO/IEC 17025 accredited, the report is dated within the last 12 months, and the lab is a separate company from the brand selling the product.
Does Wholesale Hemp Farms provide COAs? Yes. We publish COAs for every product batch on our Third Party Labs page. All testing is performed by independent accredited labs.
What's the difference between LOD and LOQ on a COA? LOD is the limit of detection, the smallest amount a test can pick up. LOQ is the limit of quantitation, the smallest amount the test can measure accurately. ND (not detected) means the result was below the LOD, which is the cleanest possible result.
If you've got a question that isn't covered here, reply to any of our emails or send a message through the contact form. Real farmers reply.
All products contain less than 0.3% Delta-9 THC on a dry weight basis and are compliant with the 2018 US Farm Bill, or products sold on this site contain 0% THC. All our hemp derived products are U.S. grown non-intoxicating cannabinoids.
FDA Disclaimer: The statements made regarding these products have not been evaluated by the Food and Drug Administration. The efficacy of these products has not been confirmed by FDA-approved research. These products are not intended to diagnose, treat, cure or prevent any disease. These products should not be used if you are pregnant or nursing. No statements are offering medical advice. Please consult a healthcare professional before use of any of our products.
