Is your clinical team making small mistakes in coding that could be costing your practice big money?
Many private practices think their coding is going well—until they do a coding audit. These audits often find problems like underpayments, denials, or even rule violations. Fixing these issues late means lost money you might never get back.
We recently helped a medium-sized primary care practice that thought everything was fine. During a review of their billing, we found a big problem: they were using incident-to billing incorrectly.
Nurse practitioners were seeing patients on their own, without a doctor in the office or a signed care plan. But the practice was billing under the doctor’s name, which gets paid at 100% of the Medicare rate. That’s against Medicare rules.
These services should have been billed under the nurse practitioner’s name at 85% of the rate. Because of this mistake, the practice might have to repay over $300,000—and now they’re under closer watch from insurance payers.
This wasn’t fraud. It was just a lack of training. But this kind of mistake is more common than people think. Let’s go over three of the most common and costly coding errors, and how to fix them.
1. Using Outdated or Nonspecific Diagnosis Codes
What’s the Problem? Every year, the ICD-10 codes get updated. These codes help explain what a patient was seen for. If your staff uses old codes, or general ones when a specific one exists, your claims could be denied or paid less.
Example: A patient comes in for their yearly physical. During the visit, their blood pressure is high. If you only use code Z00.00 (general check-up), the visit looks simple. But if you use Z00.01 (check-up with abnormal findings) plus I10 (high blood pressure), the visit looks more complex—and you can bill for more.
How to Fix It:
- Check and update your diagnosis code lists every January.
- Train your team to choose the most specific code.
- Use software or EHR tools to find the best code.
2. Missing or Incorrect Modifiers
What’s the Problem? Modifiers are extra numbers you add to a procedure code. They explain special situations, like if a service was done more than once or done along with another service. If you forget a modifier—or use the wrong one—your claim could get denied.
Example: A patient comes in to remove a wart, but also talks to the doctor about ongoing migraines. You bill for the wart removal and also for the office visit. But if you forget to add Modifier 25 to the visit code, the insurance might think it was all one service and deny payment for the visit.
Correct Billing:
- 99214-25 (office visit for migraines)
- 11720 (procedure code for the wart removal)
Common Modifier Mistakes:
- Using Modifier 25 with procedures instead of visits
- Forgetting Modifier 59 when billing two separate procedures on the same day
How to Fix It:
- Create a quick-reference sheet for the most-used modifiers in your practice
- Teach both clinical and front desk staff when modifiers are needed
- Do spot checks on claims to catch errors early
3. Undercoding Evaluation & Management (E/M) Levels
What’s the Problem? Many doctors pick a lower E/M code—like 99213 for an office visit—because they’re afraid of audits or don’t know the latest rules. But this can cause big revenue loss over time.
What Changed in 2021? Medicare updated the rules. Now, you can bill based on how much time you spend with a patient or the complexity of your medical decision-making, not just the number of body systems checked.
Example: If you spend 35 minutes talking to a patient about managing multiple health problems, you should bill 99214, not 99213. That’s what the new rules allow.
E/M Code Guide for 2024 (Established Patients):
- 99212: 10-19 minutes
- 99213: 20-29 minutes
- 99214: 30-39 minutes
- 99215: 40-54 minutes
How to Fix It:
- Use timers or EHR tools to track your visit time
- Clearly write how long you spent and what you discussed
- Give your team regular training on how to document and bill correctly
Why This Matters: If a provider sees 20 patients a week and undercodes by $35 per visit, that’s $700 a week or $36,400 a year in lost revenue.
Conclusion
Small billing mistakes can add up fast. Whether it’s outdated codes, missing modifiers, or undercoding office visits, these issues cost private practices thousands—or even hundreds of thousands—of dollars.
The good news is that all of this can be fixed. Start by checking your billing practices every few months. Train your team. Use tools to help make better decisions. And don’t wait until a payer or auditor points out a problem.
Fixing these common issues can help your practice get paid what it deserves—and stay out of trouble.
Need help reviewing your billing or training your team? We specialize in helping private practices improve their billing processes. Reach out to learn how we can help at [email protected].
