The 13 documents, compared
What each is, what it does not prove, the neutral next step, and any timing. Read against your own paperwork.
| Document | What it is | What it starts / doesn't prove | Neutral next step | Clock / keep |
|---|---|---|---|---|
| Explanation of Benefits (EOB)the processing math, not the verdictCMS_eobHCgov_internal | Not a bill — not the denial | ShowsHow the plan processed a claim — billed, allowed, plan-paid, and your share. It can reveal that something wasn't covered, which is the cue to look for the formal determination. Doesn't proveAn EOB line is not itself the adverse benefit determination; the appeal clocks run from the denial notice, not from the EOB. |
Match the EOB against the provider's bill and, if something was denied, locate the denial notice that goes with it. | Keep with the claim file |
| Denial letter / adverse benefit determinationthe clock-starterCCIIO_appealsHCgov_internal | Starts the appeal clock | ShowsThe plan's formal denial. It must state the reason for the denial, your right to an internal appeal, your right to external review, and the availability of your state's Consumer Assistance Program — and its arrival generally starts your 180-day window to file the internal appeal. Doesn't proveFinality: a first denial is the beginning of the documented process, not the end of it. |
Keep the notice and its date, read the stated reason carefully, and mark the filing deadline it creates the day it arrives. | Internal filing window runs from this notice |
| Plan internal appeal instructionsthe mechanicsHCgov_internal | The plan's own how-to | ShowsWhere and how the plan accepts appeals — required forms, the address or portal, and any internal levels. The plan documents and the denial notice together control the mechanics. Doesn't proveThe federal floor: the instructions set procedure, but they can't shorten the rights the rules guarantee. |
Follow the plan's stated process exactly — wrong-channel filings are where deadlines get missed for no reason. | Procedure lives here |
| Internal appeal requestyour filingHCgov_internal | File within 180 days | ShowsYour formal ask for the plan to conduct a full and fair review of its denial — generally due within 180 days (6 months) of receiving the denial notice, on the plan's forms or in writing with your name, claim number, and member ID. Doesn't proveApproval, or even receipt — which is what the acknowledgment and your own submission record are for. |
File in writing within the window, attach the supporting documents, and keep a dated copy of everything sent; your state's Consumer Assistance Program can file for you. | 180 days from the denial notice |
| Medical records / provider statementthe evidence, not the appealHCgov_internal | Supporting evidence | ShowsThe clinical support behind the appeal — records, test results, and a letter from the treating doctor addressing the stated denial reason. Doesn't proveA filed appeal: evidence supports the request but doesn't replace it. Sending records without the appeal filing starts nothing. |
Ask the provider for records and a statement that speaks to the denial reason, and submit them with — or referenced to — the appeal filing. | Attach to the filing |
| Urgent / expedited appeal requestthe fast trackHCgov_internalCCIIO_appeals | 72-hour decision lane | ShowsThe request to decide faster because the standard timeline would seriously jeopardize your life, health, or ability to regain maximum function — urgent-care appeals are decided within 72 hours, and in urgent situations the internal appeal and external review can run at the same time. Doesn't proveAutomatic qualification: urgency is a defined standard, and non-urgent cases run on the standard clocks. |
If the situation is urgent, say so explicitly in the filing and request the expedited track — and note that you may file the external review request simultaneously. | 72 hours · can run both stages at once |
| Internal appeal acknowledgmentproof the clock turned overHCgov_internal | Receipt, not result | ShowsThat the plan received the appeal — the reference point for the plan's own decision deadline, which runs in days from the request, not from the original denial. Doesn't proveAnything about the outcome; it confirms the review started. |
Keep it with your dated submission record, and note the decision-due date it implies. | Decision clock runs from receipt |
| Internal appeal decisionthe plan re-decidesHCgov_internalCCIIO_appeals | Written, on a deadline | ShowsThe plan's written answer to the appeal — due within 30 days when the service hasn't been received yet, 60 days when it has, and 72 hours on the urgent track. Doesn't proveThe end of the road: this is still the plan reviewing the plan. An adverse answer here is what opens the external stage. |
Read whether the decision is favorable, partial, or adverse — and if adverse, look for the final-determination language and the external-review instructions it must carry. | 30d pre-service · 60d post · 72h urgent |
| Final adverse benefit determinationthe exhaustion documentHCgov_externalHCgov_internal | Opens the external window | ShowsThe plan's final internal answer upholding the denial. It is the document that shows the internal process is exhausted, it must tell you how to ask for an external review — and it generally starts your 4-month window to request one. Doesn't proveThat the denial will stand: it ends the plan's own process, not the review path. |
Mark the external-review deadline the day this arrives, and follow the request instructions the determination itself must contain. | External window runs from this notice |
| External review requestmoving outside the planHCgov_externaleCFR_147136 | 4 months, in writing | ShowsYour written request — generally due within 4 months of the denial or final determination — that puts the case before a reviewer independent of the plan, via the federally administered process or your state's process, per your notice. A representative such as your doctor may file it for you. Doesn't proveEligibility by itself: the request undergoes a preliminary review before assignment, which the eligibility notice answers. |
File through the channel the determination names (the federal process runs through externalappeal.cms.gov), within the window, with the records attached. | 4 months from the determination |
| External review eligibility noticedoes the case qualifyeCFR_147136 | The gatekeeper answer | ShowsThe preliminary-review answer: whether the request is complete and the denial is the kind external review covers, and that the case is being assigned to an independent review organization. Doesn't proveThe merits — eligibility says the case will be reviewed, not how it will come out. |
If the notice says the request is incomplete, supply what's missing within the time it states; if ineligible, the notice explains why and what remains. | Respond within the notice's window |
| Independent review organization decisionthe binding stageHCgov_externaleCFR_147136CCIIO_appeals | Binding on the insurer | ShowsThe independent reviewer's decision — due within 45 days for standard review, 72 hours for expedited (with written confirmation within 48 hours if delivered orally). This is the stage with different power: the insurer is required by law to accept the external reviewer's decision. Doesn't proveA new claim: it decides the dispute that was submitted, on the record that was submitted. |
Keep the decision with the full file; if it overturns the denial, the plan must provide the payment or services the claim sought. | 45 days standard · 72 hours expedited |
| State / federal external review program noticewhich track applieseCFR_147136HCgov_external | Names your process | ShowsWhich external-review track governs your case — a state-run process meeting the federal standards, or the federally administered one — as stated in your denial documents. The federal rules define both tracks and the minimums each must meet. Doesn't proveIdentical procedure everywhere: state processes vary in their details within the federal floor, and your notice's instructions are the operative ones. |
Use the process your own notice names rather than a generic description; your state's Consumer Assistance Program can help identify it. | Your notice names the track |
Two stages, two different powers
The internal appeal and the external review look similar on paper — both are requests with deadlines — but they hold different power. The internal appeal asks the plan to conduct a full and fair re-decision of its own call, and the plan's answer can still be adverse. The external review moves the case to an independent reviewer outside the plan, and that decision the insurer is required by law to accept: if the reviewer overturns the denial, the plan must provide the payment or services.
The bridge between the stages is a specific document: the final adverse benefit determination. It proves the internal process is exhausted, it must contain the external-review instructions, and it starts the external clock. The one structural exception is urgency — in urgent situations, the external review can be requested before the internal process finishes, and both can run at once.
Where each clock comes from
No single deadline governs the chain — each window is started by a specific document:
- The denial notice starts the internal filing window — generally 180 days (6 months) from receiving it.
- The plan's receipt of your appeal starts the decision clock: 72 hours for urgent care, 30 days for a service not yet received, 60 days for one already received.
- The final adverse determination starts the external window — a written request generally within 4 months.
- The reviewer's receipt of the request starts the decision clock: no later than 45 days standard, 72 hours expedited.
What this page cannot determine
The chain above is the federal baseline for ACA-era private plans, and several things vary:
- Your plan's exact procedures and levels. The plan documents and your own notices control the mechanics, and they can be more generous than the floor.
- Which external-review track applies. State-run or federally administered depends on your plan type and state — your notice names it.
- Whether these rules apply at all. Grandfathered plans (created on or before March 23, 2010) are outside these appeal rights, and Medicare and Medicaid run entirely different appeal systems.
- The merits of any appeal. This page maps the documents and clocks; it cannot evaluate a denial, a treatment, or a case.
Checklists
The neutral, document-focused version — what to gather and verify, not what to argue.
File Building the appeal file
- Keep the denial notice and its date — every clock traces back to a dated document.
- Keep copies of everything you send and receive, including envelopes and portal confirmations.
- Put the claim number and member ID on every page and message.
- Get the provider's records and statement addressed to the stated denial reason.
- Submit by a method with a dated record and keep the acknowledgment.
Clock Deadline triage on each document
- Denial notice arrives → mark the 180-day internal filing date.
- Appeal filed → note the plan's decision-due date (72h / 30d / 60d).
- Final adverse determination arrives → mark the 4-month external-review date.
- Urgent situation → request the expedited track, and consider filing external review simultaneously.
- Any notice names a shorter window → the document in your hands controls.
Common wrong assumptions
- The EOB denial line is the denial letter.The adverse benefit determination is the formal notice — it must state the reason and your appeal rights, and it's the document the 180-day internal clock runs from.
- The plan's appeal decision is the final word.An adverse internal decision opens the external stage. The independent reviewer's decision is the one the insurer is required by law to accept.
- External review is just another letter to the insurer.It moves the case outside the plan to an independent review organization, through the federally administered process or your state's process — and its outcome binds the plan.
- Every appeal runs on the same leisurely clock.Urgent-care appeals are decided within 72 hours, and in urgent situations the internal appeal and external review can be filed at the same time.
- These rules cover every health plan.Grandfathered plans are outside these appeal rights, and Medicare and Medicaid have entirely separate appeal systems. Your plan documents and notices state what applies to you.
Sources
Every term and mechanism traces to a primary regulator. Rules change — the date is when each was last checked.
| Source | What it establishes | Checked |
|---|---|---|
| HealthCare.gov — Internal Appeals | File the internal appeal within 180 days (6 months) of receiving the denial notice; the plan completes urgent-care appeals in 72 hours, appeals for services not yet received in 30 days, and services already received in 60 days; a written decision is required; the final determination must say how to request external review; in urgent situations internal appeal and external review may run simultaneously; the state Consumer Assistance Program can file for you. | 2026-06-11 |
| HealthCare.gov — External Review | A written external-review request is due within 4 months of the denial notice or final determination; standard reviews are decided no later than 45 days and expedited reviews no later than 72 hours; the insurer is required by law to accept the external reviewer's decision; the federal process runs through externalappeal.cms.gov, and a representative such as your doctor may file. | 2026-06-11 |
| CMS CCIIO — Appealing Health Plan Decisions | The denial notice must state the reason for denial, the right to internal appeal, the right to external review, and Consumer Assistance Program availability; internal appeal decisions are due in 72 hours (urgent), 30 days (not yet received), or 60 days (received); if the external reviewer overturns the denial the insurer must provide the payments or services; plans created on or before March 23, 2010 may be grandfathered and outside these rights. | 2026-06-11 |
| 45 CFR § 147.136 — Internal Claims and Appeals and External Review Processes | The regulatory backbone: state external-review processes must require the IRO's written decision within 45 days of receiving the request (72 hours expedited, with written confirmation within 48 hours of an oral decision); expedited review covers emergency and jeopardy circumstances; a federally administered process exists as the alternative track. | 2026-06-11 |
| CMS — Explanation of Benefits (EOB) | The EOB's role and fields — billed, allowed, plan-paid, patient responsibility — and that an EOB is not a bill; the formal denial determination is a separate notice. | 2026-06-10 |