Complaint Letter to a Hospital Billing Department

Billing Errors vs Service Complaints

Hospital billing complaints fall into two broad categories, and your letter should make clear which one you are writing about.

Billing errors include incorrect charges, duplicate charges, charges for services you did not receive, incorrect insurance coding, or failure to apply your insurance properly. These are factual disputes. Something on the bill is wrong, and you want it fixed.

Service complaints involve the quality of care, staff behavior, wait times, or communication failures. These matter too, but they follow a different path (typically through patient relations, not the billing department).

This post focuses on billing. If your letter involves both, separate the issues clearly: address the billing dispute with the billing department, and the service complaint through the hospital's patient relations or patient advocate office.

Most hospital billing errors are not intentional. Medical billing is genuinely complex, with hundreds of procedure codes, insurance negotiations, and manual data entry points where mistakes happen. But the fact that errors are common does not mean you should accept them. Roughly 80% of medical bills contain at least one error, according to medical billing advocacy organizations. Checking your bill carefully is not being difficult. It is being responsible.

Requesting an Itemized Bill and Explanation

If you received a summary bill (a single total or a handful of line items), your first step is to request a fully itemized bill. You have the right to this under federal law.

Write: "I am requesting a fully itemized bill for services provided on [date(s)] at [hospital name], including all CPT codes, descriptions of each service or procedure, individual charges, and any adjustments applied. My patient account number is [number]."

An itemized bill breaks the total into every individual charge: each medication, each lab test, each supply item, each professional fee. This is where you will find the errors, because summary bills are designed to be easy to read, not easy to audit.

What to Look For

Once you have the itemized bill, check for:

Duplicate charges: The same service listed twice with the same code and date
Unbundling: Procedures that should be billed as one code split into multiple codes (which costs more)
Charges for services you did not receive: A common example is being charged for a room on the day of discharge
Incorrect quantities: Charged for five doses of medication when you received two
Insurance not applied: Your insurance should have been billed first. If the bill shows the full charge without insurance adjustments, the hospital may not have submitted it to your insurer

Compare the bill against your own records. What appointments did you attend? What procedures were performed? What medications were administered? If you are unsure, request your medical records for the same dates and cross-reference.

Disputing Incorrect Charges in Writing

Once you have identified specific errors, put the dispute in writing. Phone calls to billing departments are fine for asking questions, but disputes should be documented.

Your letter should include:

Your name, date of birth, and patient account number
The specific charges you are disputing (include the CPT code, description, date of service, and amount for each)
Why each charge is incorrect (duplicate, not received, wrong quantity, insurance not applied)
What you believe the correct charge should be (if you know)
A request for the billing department to review and correct the listed charges

For example: "I am disputing the following charges on my itemized bill dated November 30, 2026:

CPT 99213 (Office visit, established patient), billed at $285.00 on October 15. This charge appears twice. I had one visit on this date.
Revenue code 0250 (Pharmacy), $47.00 per unit, quantity 4. Per my discharge paperwork, I received two doses of this medication, not four.
Revenue code 0120 (Room and board, semi-private), $1,850.00, dated October 18. I was discharged at 9:00 AM on October 18 and should not be charged for a full day."

This level of specificity makes it easy for the billing department to locate and verify each issue. Vague disputes ("this bill seems too high") give them nothing to investigate.

Referencing Financial Assistance Programs

If the bill is correct but you cannot afford to pay it, most hospitals have financial assistance programs. Under the Affordable Care Act, nonprofit hospitals are required to have a written financial assistance policy and to make it available to patients.

You can ask about financial assistance in the same letter that disputes charges, or in a separate letter. Either way, include:

A statement that you are requesting information about the hospital's financial assistance program (sometimes called "charity care")
A brief description of your financial situation (you do not need to give extensive detail at this stage, just enough to explain why the bill is a hardship)
A request for an application or eligibility information

"In addition to the billing disputes above, I am requesting information about [Hospital Name]'s financial assistance program. My current financial situation makes it difficult to pay this balance in full, and I would like to explore all available options before the account is sent to collections."

Hospitals are generally required to respond to financial assistance requests before referring your account to a collection agency. If your account has already been sent to collections, mention that in your letter and ask whether financial assistance can still be applied.

For more guidance on writing about financial hardship to medical providers, see LetterLotus's guide to medical debt hardship letters.

Negotiating the Balance

Even if you do not qualify for formal financial assistance, hospitals often negotiate. You can request:

A payment plan with no interest
A reduced balance for prompt payment ("I can pay $X if the remaining balance is forgiven")
A reduction to the Medicare or Medicaid rate (what the government would pay for the same services, which is typically much less than the listed price)

Put your offer in writing. "I am willing to pay $[amount] as a lump sum if the remaining balance of $[amount] is forgiven. I believe this is reasonable given [brief reason]."

When to Contact a Patient Advocate

If your billing dispute is not resolved through the billing department, ask for the hospital's patient advocate or patient ombudsman. This is a person (or office) whose job is to help patients resolve complaints, including billing issues.

Patient advocates can:

Review your case with more authority than a billing representative
Facilitate communication between you, the billing department, and your insurance company
Help you access financial assistance programs
Escalate issues internally

If the hospital does not have a patient advocate, or if the advocate cannot resolve your issue, your next step is to file a complaint with your state's Department of Health or the agency that licenses hospitals in your state. For insurance-related billing issues (your insurer did not cover something you believe should be covered), file with your state insurance commissioner.

Keep copies of every letter you send and every response you receive. If the dispute is eventually resolved in your favor, request written confirmation that the corrected balance is reflected on your account and that no collection activity will occur on the disputed amount.

Getting Started

Medical billing disputes can feel overwhelming, especially when you are recovering from a health issue at the same time. But the process is straightforward: get the itemized bill, identify the errors, put the dispute in writing, and follow up.

If you need help organizing a billing complaint letter, LetterLotus's complaint letter questionnaire helps you structure the key details so your dispute is clear and documented from the start.