What to do when insurance denies a claim starts with the denial notice and the explanation of benefits: find the stated reason, then file an internal appeal within 180 days (6 months) of receiving notice.
The sections below sort the problem by type and then walk through the paperwork, calls and deadlines. For the full filing process, see how to appeal a health insurance denial. For the causes behind refusals, see why do health insurance companies deny claims.
Start by sorting the problem
The first decision is which kind of problem you have, because each kind leads to a different first call. A patient-advocacy guide from Umbra Health Advocacy notes that a denial can happen before service, when the plan denies the authorization, or after service, when the plan denies the claim. Reduced payments and bills that disagree with the plan’s statement are related problems with their own fixes.
- The plan would not approve care in advance. This is a prior authorization problem. Plans can require patients or their providers to seek approval before certain procedures, tests and prescriptions, as The Post and Courier reports. Your doctor’s office usually drives this one, so call it first. The guide on what is prior authorization explains the process.
- The plan refused to pay for care you already received. Start with the explanation of benefits, find the stated reason, and decide whether it is a paperwork problem or a coverage decision.
- The plan paid, but less than you expected. Check whether the provider was in network, whether the claim was coded correctly and how your own cost sharing was applied. The guide on deductible vs copay vs coinsurance helps with the last of these.
- The provider’s bill does not match the plan’s statement. This is a billing dispute rather than a coverage dispute. Work through how to dispute a medical bill alongside your statement.
- You are not sure the provider was in network. Confirm this before anything else, because a network problem changes the argument. The steps are in how to check if a doctor is in network.
Criteria that decide your path
Three questions narrow the options quickly. First, is the care urgent? Urgent cases run on much shorter clocks, covered in the timeline section below. Second, has the care already happened? Appeals for services already received and for services not yet received follow different decision times. Third, is the stated reason a clerical error or a judgement about the treatment? A clerical error is usually fixed by the provider’s billing office, while a judgement about the treatment needs a formal appeal backed by clinical reasoning.
Reading the explanation of benefits
An explanation of benefits (EOB) is the plan’s statement of what it did with a claim. It is where a denial first becomes visible. The Healthcare Consumer Navigator Center explains that denial reasons and codes are documented on the EOB statement, so the reason you need is usually already in your hands.
Read the EOB with the provider’s bill beside it. Match the date of service, the provider name and each service line. Then look for the entry that shows what was denied and the code or wording that explains why. That reason determines the rest of your plan. A code pointing to a missing approval sends you to the provider about prior authorization. A code pointing to medical necessity sends you toward a clinical appeal. A code that looks like a data problem sends you to the billing office. The spoke on how to read an explanation of benefits goes line by line through a typical statement.
Treat every EOB as evidence. HealthCare.gov lists the Explanation of Benefits forms or letters showing what payment or services were denied among the papers to keep for an appeal. Keep the originals, and note the date each one arrived, because the appeal window runs from receipt of the denial notice.
Why claims are denied or paid less
Denials fall into a few recognisable groups, and the group tells you who should act. Sorting your denial into one of them is the most useful thing you can do before you pick up the phone.
- Not medically necessary. HealthCare.gov lists a finding that the requested service or treatment is “not medically necessary” among the denial reasons that can be appealed. This is a judgement call, and your clinician’s reasoning carries the most weight.
- Out of network. HealthCare.gov also lists receiving services from a provider or facility that is not in the plan’s approved network as an appealable denial reason. Before filing, check your plan documents and confirm whether the provider was in network on the date of service.
- Coding and billing errors. Umbra Health Advocacy points out that coding errors, missing modifiers, incorrect information or duplicate billing can all trigger denials. These are often corrected by the provider, who resubmits the claim, rather than by arguing with the plan.
- Missing precertification. The Healthcare Consumer Navigator Center notes that certain medical services require the healthcare provider to precertify the service. If that step was skipped, the claim can be refused even though the care itself was covered.
When the claim was paid at a reduced amount
A reduced payment is not always a denial. Part of the claim may have been denied for one of the reasons above, which makes the unpaid portion appealable like any other denial. An out-of-network provider is a common explanation, and a coding problem on one line can reduce the total. The EOB shows which lines were paid and which were not. Compare those lines with the bill, and ask the plan to explain any gap the statement does not account for. If the difference comes down to how your deductible, copay or coinsurance was applied, the plan has applied your benefits rather than denied anything, and an appeal will not change the result. If the plan seems to have applied them wrongly, ask it to explain the calculation line by line.
If you are covered by more than one plan, the order in which the plans pay can also change what each one covers. The guide on how does coordination of benefits work explains that situation.
The first calls: provider and insurer
Make calls before writing anything formal. A short call to each side often tells you whether you face a quick fix or a real appeal. Write down the date, the name of the person you spoke to and what they said.
Call the provider’s billing office
Start here when the reason on the EOB looks clerical. Ask whether the claim was coded correctly, whether a modifier was missing and whether any service was billed twice. Ask for an itemized bill so you can see every charge and check it against the plan’s statement. If the problem is a prior authorization that was never obtained or was filed incorrectly, ask the office what it can do to correct it. The provider is often the party able to resubmit.
Call the insurer
Ask the plan to state the specific reason for the denial and to identify the rule or policy behind it. The advice from Umbra Health Advocacy is to ask for the exact criteria used to review your request. Those criteria become the target of your appeal, because you can answer each one with evidence from your medical record. Ask how to file an appeal, where to send it and what the plan’s own deadline is, then compare that with the federal timelines below.
Hold payment while the question is open
If you have received a bill for the disputed amount, the Healthcare Consumer Navigator Center advises that you not pay the bill until you are satisfied with the outcome of the appeal. Tell the provider’s billing office that an appeal is in progress so the account does not move forward without your knowledge. If the account does reach a collection agency, the guide on do medical bills affect credit score covers what that can mean.
Records that support an appeal
An appeal succeeds or fails on its paperwork. Umbra Health Advocacy’s direction is blunt: save every EOB, bill, letter and email. Keep the denial notice, your insurance card information, the provider’s bill, notes from every call and any approval or authorization number you were given.
Your medical record is the second pillar of the file. Visit notes, test results and referral letters can show why a treatment was needed and what was already tried. The guide on how to request medical records explains how to ask for them. Request them early, since the appeal window starts when you receive the denial notice, not when the records arrive.
A letter from your clinician
When the denial rests on medical necessity, a letter from the treating clinician is often the strongest single document. It should describe your condition, the treatment, and why the treatment is needed for you. The guide on how to get a letter of medical necessity covers how to ask for one. The Post and Courier also describes a peer-to-peer review, which lets your doctor discuss your case over the phone with a medical professional at the insurer. Ask your doctor’s office whether that option is available for your denial.
Organise the file so you can find it
Use a binder or a single digital folder with dividers for the denial notice, EOBs, bills, correspondence, call notes and medical records. Put items in date order within each section. When a plan representative asks for a document, you can send it the same day.
Federal appeal timelines
The deadlines below come from HealthCare.gov’s guidance on internal appeals. They are the figures to plan around, and your denial letter and plan documents should state the dates that apply to your claim. The filing deadline is the one that cannot be recovered, so mark it on a calendar the day the notice arrives.
| Situation | Timing | Planning use |
|---|---|---|
| Filing an internal appeal | Within 180 days (6 months) of receiving the denial notice | Treat this as the outer limit. Aim to file well before it, since gathering records and a clinician’s letter takes time. |
| Plan’s decision on a prior authorization request | Within 15 days of the request | If no answer arrives in this window, contact the plan and the provider’s office. |
| Plan’s decision on a medical service already received | Within 30 days | Expect a written decision in this window and log the date it arrives. |
| Plan’s decision in an urgent care case | Within 72 hours | Do not wait on routine processing when delay could affect your health. Tell the plan the case is urgent. |
| Internal appeal for a service not yet received | Completed within 30 days | Use this when the appeal is about approving care before it happens. |
| Internal appeal for a service already received | Completed within 60 days | Expect a longer wait and keep paying attention to any bill the provider sends. |
| Expedited appeal | Final decision at least within 4 business days after the request is received | Ask for expedited handling when the delay of a standard appeal would be harmful. |
These figures come from the HealthCare.gov internal appeals guidance. The Post and Courier’s reporting is consistent on the main point, noting that most health plans give you only six months to appeal the decision.
Filing the internal appeal
An internal appeal asks the insurer itself to review its decision. Send it in writing, within the filing window, and keep proof of the date and method of delivery. State the claim, the date of service, the denial reason and the outcome you are asking for. Then answer the reason directly. If the denial said the treatment was not medically necessary, point to the clinician’s letter and the specific parts of your record that support the treatment. If the denial was for an out-of-network provider, explain the circumstances and attach any evidence that bears on the network status.
- Read the denial notice and the EOB, and write the stated reason in one sentence.
- Gather the notice, EOBs, bills, call notes and relevant medical records.
- Ask the clinician for a supporting letter where the reason is medical.
- Write the appeal letter, answering the plan’s stated reason point by point.
- Send it by a method that gives proof of delivery, and keep a full copy.
- Follow up before the decision window closes if you have heard nothing.
If the case is urgent, say so at the start of the letter and on the phone, and ask the plan for expedited handling. The decision-time rules in the table apply, and a short standard timeline is not a reason to wait if care is time-sensitive.
Try to resolve the cause as well as the denial
An appeal answers the plan’s decision, but a billing error might also be corrected at the source. If the provider found a coding or modifier mistake, ask for a corrected claim and mention it in your appeal. If you need to talk about a balance that remains after the plan has paid what it will, the guide on how to negotiate a medical bill covers that stage.
External review and state help
An internal appeal is not the end of the road. According to HealthCare.gov, if your insurance company still denies your claim, you can file for an external review. That brings in a reviewer who is not the insurer. In urgent situations, HealthCare.gov adds that you can ask for an external review at the same time as your internal appeal, so you do not have to wait for the insurer to finish first.
You do not have to handle this alone. HealthCare.gov states that the Consumer Assistance Program in your state can file an appeal for you. State insurance departments are also a natural starting point for questions about how your plan is regulated and where to take a complaint about how it handled a claim.
Related situations and next steps
Some denials sit inside a larger coverage question. The paths below cover the most common ones.
- You are still choosing coverage. If a denial has made you question your plan, how to choose a health insurance plan sets out the comparison points to weigh, including how the plan handles approvals and networks.
- You are on Medicare. Gaps in original coverage are sometimes filled by private plans. The guide on what is a medicare supplement plan explains how that works.
- Your coverage changed after leaving a job. Continuation coverage brings its own paperwork. See how does cobra health insurance work before assuming a denial reflects the plan’s rules.
- Your balance is the problem. After an appeal, a remaining balance can still be questioned or negotiated, using the billing guides linked above.
Frequently asked questions
Should I pay the bill while an appeal is pending?
The Healthcare Consumer Navigator Center advises not paying the bill until you are satisfied with the outcome of the appeal. Tell the provider’s billing office an appeal is in progress.
Can my doctor help with the appeal?
Yes. A clinician can write a supporting letter and, where the plan allows, take part in a peer-to-peer review. The Post and Courier describes this as a phone discussion between your doctor and a medical professional at the insurer.
Who can file an appeal for me?
Under federal guidance on HealthCare.gov, a Consumer Assistance Program in your state may file the appeal on your behalf. That is a good option if the paperwork feels overwhelming.
Can an urgent case be sped up?
Yes. HealthCare.gov describes expedited appeals, with a final decision at least within 4 business days after the request is received. An external review can also be requested at the same time as the internal appeal in urgent situations.