Free Medical Bill Checker — Compare Your Bill vs EOB

Use our free medical bill checker to compare your medical bill to your EOB. Enter the amounts from both documents, and we'll instantly identify billing errors, duplicate charges, and potential balance billing issues—no signup required.

You'll need: your provider bill + your insurance EOB

How it works: Enter line items → click Analyze → get a summary

Privacy: Anonymous until you choose to save by email

Takes ~60 seconds. No signup.

CPT Code	Billed ($)	Allowed ($)	EOB Says You Owe ($)
Enter CPT code

Why Your Medical Bill May Not Match Your EOB

Your medical bill and Explanation of Benefits (EOB) should align, but often they don't. Here are the most common reasons:

Duplicate Charges: Your provider may bill you twice for the same service due to billing system errors or manual data entry mistakes.
Coding Errors: Incorrect procedure or diagnosis codes can result in higher charges than what your insurance approved or what you owe.
Balance Billing: Out-of-network providers or specialists may bill you beyond what your insurance considers reasonable, violating balance billing protections in some cases.
Out-of-Network Issues: If your visit was out-of-network, your responsibility may be much higher than in-network rates shown on your EOB.

If you find discrepancies, it's important to dispute them early. The sooner you catch a billing error, the better. Learn more about the process and your legal rights in our guide on what happens if you don't pay a medical bill.

How to Compare a Medical Bill to an EOB

Start by locating the billed amount on your provider statement. Then review your Explanation of Benefits (EOB) from your insurance company. Compare the allowed amount and the patient responsibility listed on your EOB to what the provider is requesting. If your provider is charging more than your EOB says you owe, it may indicate duplicate billing, coding issues, or possible balance billing. Reviewing both documents side by side helps you catch mistakes before paying.

Learn More: Medical Bills, EOBs, and Your Rights

Understanding the relationship between your medical bill and EOB is the first step to protecting yourself from billing errors. For deeper insights, check out our comprehensive guides: learn about the EOB vs medical bill guide to understand exactly how these documents differ, and our breakdown of what happens if you don't pay a medical bill to learn your rights and obligations.

Quick Resources

EOB vs Bill Guide

Understand the difference between your bill and EOB and how they should align.

How to Negotiate Bills

Step-by-step guidance on negotiating medical bills with providers.

Dispute Toolkit

Templates and best practices for disputing billing errors formally.

What If You Don't Pay

Timeline and rights when bills go to collections.

Frequently Asked Questions

Common signs of medical bill errors include duplicate charges, incorrect procedure codes, charges for services not received, and amounts that don't match your Explanation of Benefits (EOB). Our free checker identifies these instantly.

Yes! CostKits offers a completely free medical bill checker that analyzes your bills for errors, duplicate charges, and overcharges. No signup, no credit card, and anonymous until you choose to save by email.

The most common errors include duplicate charges (same service billed twice), upcoding (billing for more expensive procedures), unbundling (charging separately for services that should be combined), and charges for services not received.

Your EOB (Explanation of Benefits) comes from your insurance and shows how your claim was processed. Your medical bill comes from the provider requesting payment. These amounts should align. If they don't, there may be a billing issue.

Medical bills follow a specific timeline. Most providers give you 30-180 days before collections begins. You have rights under the FDCPA once collectors are involved.

Your analysis is anonymous until you choose to save by email. We follow HIPAA-aligned practices to protect your information. We don't share your data with third parties without your explicit consent.