CPT 87491

Understanding Your Chlamydia Test Bill (CPT Code 87491)

CPT code 87491 is the billing code for a chlamydia test that uses advanced DNA detection methods. This is one of the most accurate ways to test for chlamydia infections.

What Medicare Pays vs. What You Might Be Charged
Category Amount
Medicare Allowed Rate What Medicare approves for this service $35.09
Typical Billed Amount What providers commonly charge $50 – $250
Potential Markup How much more you might pay vs. Medicare rate 612% above Medicare
Why the difference? Providers set their own prices. Without insurance, you may be billed the full amount. Even with insurance, your co-pay is often based on the provider's charge — not the Medicare rate.

What CPT Code 87491 Means

When you see CPT code 87491 on your medical bill, it means you received a chlamydia test using what's called an "amplified probe" method. This is a highly accurate laboratory test that detects the DNA of chlamydia trachomatis bacteria in your sample.

Your doctor might order this test if you're having symptoms like unusual discharge, burning during urination, or pelvic pain. It's also commonly used for routine screening during annual exams, especially for sexually active individuals under 25 or those with new partners.

The test typically uses a urine sample or a swab from the affected area. The "amplified probe" technology makes this test extremely reliable, which is why it's the preferred method for chlamydia detection in most medical settings.

What to Expect on Your Bill

For CPT code 87491, you can expect to see charges ranging from $50 to $250, depending on your healthcare provider and location. The Medicare reimbursement rate for this test is $35.09, which gives you an idea of the baseline cost.

On your bill or explanation of benefits, you might see this listed as "chlamydia test," "STD screening," or the full description "infectious agent detection, chlamydia trachomatis, amplified probe." The code 87491 should appear somewhere on the billing statement.

If you have insurance, your out-of-pocket cost will depend on your plan's coverage for preventive care and laboratory services. Many insurance plans cover STD screening at 100% when it's considered preventive care, but you may have a copay or need to meet your deductible if it's diagnostic testing.

How to Verify Your Charges Are Correct

To check if your CPT 87491 charges are reasonable, first confirm that you actually received a chlamydia test during your visit. If the charge seems high (over $250), contact your provider's billing department to ask for an itemized explanation.

Sometimes this code gets confused with similar tests like CPT 87591 (gonorrhea test) or CPT 87490 (a different type of chlamydia test). Make sure the code matches the test you received. If you had multiple STD tests done, you should see separate codes for each one.

If you believe you've been incorrectly charged, gather your medical records from the visit and contact your healthcare provider's billing department. They can review what tests were actually performed and correct any errors. You can also contact your insurance company if you think they processed the claim incorrectly.

Codes Often Confused With CPT 87491

CPT 87591 CPT 87490

Frequently Asked Questions

How much does a chlamydia test cost?
The cost for CPT code 87491 (chlamydia test) typically ranges from $50 to $250. Your actual cost depends on your insurance coverage, with many plans covering STD screening as preventive care at no cost to you.
Is CPT 87491 covered by insurance?
Most insurance plans cover chlamydia testing, especially when it's for routine screening or preventive care. Coverage may vary if the test is diagnostic (ordered because of symptoms) versus preventive screening.
What's the difference between CPT 87491 and other chlamydia test codes?
CPT 87491 uses amplified probe technology, which is the most accurate method for chlamydia detection. CPT 87490 is a different type of chlamydia test, while 87591 is for gonorrhea testing, not chlamydia.