When a patient drops by the lab solely for a wellness blood draw, no new office visit occurs that day. The provider has already examined the patient (either in the clinic or via telehealth) and issued a standing order for routine screening. Because a fresh exam note is missing, the insurer tends to review the claim more closely to confirm that coding and documentation match the service.
➜ If the blood work is purely preventive, such as an annual cholesterol or fasting glucose test, the biller assigns a Z-code like Z00.00 for a general check-up or Z13.6 for heart-disease screening. These codes mark the test as routine prevention, and most plans cover the cost entirely under the Affordable Care Act.
➜ When the draw is meant to follow up on an existing issue, the biller selects a condition code. For example, E78.5 for high cholesterol or R53.83 for fatigue. This choice signals medical necessity, so standard deductibles and co-pays usually apply.
➜ Before submitting the claim, the lab team keeps the signed order in the chart, records a brief note explaining the reason for the test, confirms patient consent, and logs the collection time.
So, you see that with intent, codes, and notes aligned… denials are less likely and payment tends to arrive on schedule!
When does this billing scenario happen?
This situation applies when:
- the patient has no same day consultation. They walk in just for the blood draw, with no new exam or talk with the clinician.
- the lab order is already in the chart. It was placed during a previous visit or sent through the online portal.
- the tests are preventive rather than diagnostic. Panels such as cholesterol, fasting glucose, and vitamin D simply check overall health.
For example, during an annual wellness visit last month the family doctor ordered routine labs and asked the patient to return later for the draw. Today the patient comes in, provides the sample, and leaves. There is no time in an exam room. Because this is a standalone preventive draw, the claim must rely on the earlier order and the correct preventive codes, not a new visit note.
How to Bill for Wellness Lab Draws: A Step-by-Step Breakdown for Clinics
When a patient comes in only to get labs drawn for preventive screening (like cholesterol or blood sugar), billing correctly becomes decisive. This guide supports accurate, efficient, and compliant billing for routine lab services such as lipid panels, glucose testing, and HbA1c while staying aligned with insurance guidelines. Here’s how to do it properly step by step:
Step #1: Check Coverage Criteria for Direct Lab-Only Visits
Preventive tests like lipid panels or fasting glucose are not handled the same way by every health plan. A lab that is preventive in the medical sense can still be unpaid if it is done without a visit. Skipping this check often leads to claim denials, surprise bills for the patient, and lost revenue for the clinic.
Here’s what to do before the patient’s appointment:
➜ Verify benefits
- Call the plan or use its online portal.
- Look up preventive benefits and lab services for the patient.
- Ask clear questions such as “Under what conditions is this test covered?” instead of “Is it covered?”
➜ Confirm lab-only coverage
- Many insurers cover preventive labs only when they happen during a wellness or evaluation visit.
- Ask if the plan will pay when the patient comes in only for the draw.
- Example wording: “Does the plan cover a lipid panel as preventive if the patient has no same day visit?”
➜ Document every answer
- Note the name of the plan contact or the portal reference.
- Record any rules about required visits, bundling, or prior approval.
- Share these notes with front desk and billing staff so everyone follows the same guidance.
Step #2: Pick the Right Preventive Codes
After verifying that the plan covers lab-only visits, the next task is to show the payer why the tests were ordered. Insurers read the ICD-10 diagnosis code first, then look at the CPT service codes. If the diagnosis points to a known condition, the claim will be treated as diagnostic. If the diagnosis points to preventive screening, the plan is far more likely to pay the full amount.
Start by matching each preventive test with a screening Z-code:
- Z00.00 — General adult exam with no abnormal findings. Use this code only when the blood work was ordered during an earlier wellness check.
- Z13.220 — Screening for cholesterol or lipid disorders. Pair this with a lipid panel CPT 80061.
- Z13.1 — Screening for diabetes mellitus. Pair this with glucose CPT 82947 or HbA1c CPT 83036.
These codes make it clear that the patient is healthy and the draw is routine.
➜ Connect every CPT with a preventive diagnosis
A typical lab bundle might include:
- 36415 Venipuncture
- 80061 Lipid panel
- 82947 Glucose test
- 83036 HbA1c
Attach only preventive Z-codes to each line. Even the venipuncture must carry the same diagnosis, or the claim looks diagnostic.
➜ Avoid problem-oriented codes
Skip codes such as E78.5 (hyperlipidemia) or R73.9 (abnormal glucose). They suggest the patient already has a condition, which can trigger a denial or push the bill back to the patient.
➜ Clean up EMR templates
Use language that reinforces preventive intent:
- “Ordered for routine annual screening.”
- “Patient is asymptomatic and here for preventive care.”
- Avoid phrases like “evaluate cholesterol” or “rule out diabetes,” which sound diagnostic.
Step #3: Bill Only for the Work That Was Actually Done
First, submit charges only for the lab services provided that day. If the patient never spoke with a clinician, an Evaluation and Management code should not appear on the claim. Adding an E and M line when no medical decision-making or exam took place can trigger denials, audits, or even refund demands.
➜ What to leave off the claim
- Any office-visit or consultation code. A quick blood draw by a nurse or phlebotomist is not a visit.
- Any lab code that was not performed. If HbA1c was not ordered, skip it.
➜ What to include only when performed
- 36415 — Venipuncture for the blood draw
- 80061 — Lipid panel for cholesterol screening
- 82947 — Fasting glucose for diabetes screening
- 83036 — HbA1c for long-term glucose control
Attach the correct preventive Z-code to every CPT line. For example, pair 80061 with Z13.220 and 82947 with Z13.1. Match 36415 to the same preventive diagnosis so the entire claim tells a single, clear story: this encounter was routine screening, not diagnostic follow-up.
When the codes and documentation line up, the payer sees an honest, compliant claim and payment moves through without extra questions.
Step #4: Show the Preventive Purpose in the Notes
Insurers read the chart as closely as the claim. A single sentence can shift a preventive screen into a diagnostic work-up, and that shift often means a denial. Clear language that explains the draw was ordered for routine screening keeps the claim on solid ground.
Here are some key details to place in the patient’s chart:
1). Name of the ordering clinician
List the doctor, NP, or PA who approved the labs even if no visit occurred that day. This proves a clinical decision was made for preventive care.
2). Wording that confirms preventive intent
Use phrases such as:
- “Ordered as part of routine preventive screening.”
- “Patient is asymptomatic and presents for wellness bloodwork.”
- “Labs follow the patient’s established wellness plan.”
3). Phrases to leave out
Avoid wording that sounds diagnostic. Examples to skip include:
- “Rule out cholesterol disorder.”
- “Evaluate glucose abnormalities.”
- “Follow up on elevated levels.”
- “Patient complains of fatigue, consider diabetes.”
These lines imply symptom-driven testing and may require an E and M visit.
➜ Simple EMR habits that help
- Add a smart phrase that drops preventive language into every lab-only order.
- Remind nurses and medical assistants that their notes affect billing as much as the claim form.
- Review sample documentation in staff huddles so everyone sees good and bad examples.
Specific, preventive language paired with the correct Z codes shows the lab work was routine. When the story in the notes matches the story on the claim, insurers have little reason to deny payment.
Step #5. Keep an Eye on How the Insurer Responds
So you sent the claim. Great! Now what? First, watch every explanation of benefits that lands in your inbox. Next, jot down whether the claim was paid, under-paid, or denied. Also note any reason codes the insurer gives. Over time, these notes will show you patterns you can fix before the next batch of claims goes out.
Three slip-ups to catch right away ⬇️
1. Dropping Modifier 25 on a lab-only visit
Modifier 25 tells the payer a separate office visit happened that same day. If the patient only rolled up a sleeve for blood work, no real visit took place, so leave this modifier off. Using it when nothing was examined can raise audit flags.
2. Assuming every preventive lab is covered
Some plans pay for screening labs only when they come with a full wellness exam. Others limit coverage to once a year or require the clinician to see the patient on the draw day. Before each visit, call or check the portal to make sure the lab-only draw is actually covered.
3. Treating all plans as if they were the same
Even two patients with the same carrier can have different benefits. Age, employer group, and plan type all change the rules. Because of that, verify benefits for every patient every time.
➜ Easy habits that cut future denials
- Keep a shared cheat sheet of each payer’s preventive lab rules.
- Teach front-desk staff to ask pointed benefit questions, such as “Does this plan cover a lab-only draw?”
- Save reference numbers or portal screenshots in the chart so you have proof if there is a dispute.
- Review denial trends once a month and tweak your process right away.
Outsource Your Wellness Lab Billing To Lab Billing Services Provider
Billing for routine lab draws (like checking cholesterol or blood sugar) should be simple. But as you know, insurance companies often turn it into a guessing game. You might bill CPT 36415 for the blood draw and use a preventive code like Z00.00 or Z13.220, but if one detail is off or the payer has a special rule, your claim can be denied or delayed.
At Lab Billing Services, our job is to stop that from happening. We help labs like yours get paid faster and cleaner by handling the billing from start to finish. Our certified team knows exactly how to match CPT and ICD codes correctly, double-check documentation, and follow each payer’s unique policies—so you don’t have to.
Instead of spending hours on hold or fixing rejected claims, you can stay focused on your lab work while we take care of the billing.
Curious how it all works? Book a free call with one of our billing specialists and see how easy we can make it for your team.
