---
title: "UnitedHealthcare of Mississippi appeal form and deadline"
url: "https://denialfacts.com/insurers/unitedhealthcare-of-mississippi-inc--ms"
publisher: "Axion Labs — Denial Facts"
checked: "2026-11-04"
dataset_fixity: "sha256-cda2f9b89c8dde2a74989a35dbe7c0d08ff35dac5456484dc1c03c1b181a67b6"
---

# UnitedHealthcare of Mississippi denied your claim. Here is your deadline.

Denied by UnitedHealthcare of Mississippi? Your two appeal deadlines dated from your notice, a free letter, and its 21.7% denial rate.

## Figures

| Figure | Value |
| --- | --- |
| In-network denial rate | 21.7% |
| Claims denied | 93,567 |
| Plans in Mississippi | 15 |
| Internal appeals filed | 124 |
| Internal overturn rate | 37.1% |
| In-network claims received | 431,692 |
| External reviews filed | 0 |
| External overturn rate | not reported |
| National denial rate | 15.7% |

## External-review route

**State-run process.** Mississippi runs its own external review process meeting the federal standards, so an independent review there is handled through the state program rather than the federal one. This route is the one for insured plans, Marketplace, individual, and employer plans where an insurance company carries the risk. If your coverage is through a job and the employer pays the claims itself (a self-funded or self-insured plan, which is 63% of covered workers), the state process does not apply to you whatever your state operates, and your external review goes through the federal process instead. Your denial letter names your route; if it does not, ask your plan in writing whether the plan is self-funded.

## Denials by reason

| Reason | Claims | Share of this insurer's categorized denials |
| --- | --- | --- |
| Other reasons | 50,518 | 34.3% |
| Provider out of network | 37,335 | 25.4% |
| Member not covered | 20,284 | 13.8% |
| Administrative reason | 14,108 | 9.6% |
| Referral required | 12,563 | 8.5% |
| Service excluded from the plan | 12,263 | 8.3% |
| Benefit limit reached | 45 | 0% |

## UnitedHealthcare of Mississippi in Mississippi, at the top of the page

Mississippi

Your two dates, free

Date on your denial notice

Who pays your claims?

A job, an insurance company pays the claims

A job, my employer pays the claims itself (self-funded)

A job, I do not know which

Marketplace / individual plan I bought myself

Medicare, Medicaid, TRICARE, VA or IHS

Which state?

The reason your letter gives

I'm not sure, I'll paste the sentence later

Not medically necessary
Provider out of network
Service excluded from the plan
Experimental or investigational
Referral required
Benefit limit reached
Member not covered
Administrative reason
Other reasons

Show my two dates, free

Put in the date on your UnitedHealthcare of Mississippi, Inc. notice and get both federal deadlines as calendar dates.

Free, for a UnitedHealthcare of Mississippi, Inc. denial in Mississippi, and it runs entirely in your browser. The date, the plan type and the state you pick are never sent to us and never stored.

UnitedHealthcare of Mississippi, Inc. denied 93,567 of 431,692 in-network claims in Mississippi; every one of those denials had these same two dates on it. Across Mississippi as a whole the insurers in this file denied 11.2% of in-network claims, 1,141,675 of them, and 1,357 were appealed.

Or let the [$29 Appeal Kit](/appeal-kit) date each step and write the claim-file and external-review requests.

UnitedHealthcare of Mississippi, Inc. denied 21.7% of in-network claims in Mississippi, 93,567 claims out of 431,692.

By [Axion Labs](/about) · August 19, 2026, updated November 4, 2026

Further down this page, after the free steps: the paid next step .

United keeps denying my claims. I'm up to my ears in medical debt and I make close to nothing.

We hear this most. [r/HealthInsurance, thread title](https://www.reddit.com/r/HealthInsurance/comments/1i8epgx/united_keeps_denying_my_claims_im_up_to_my_ears/) , read September 3, 2026.

The number nobody else publishes. Not one of the 93,567 denials UnitedHealthcare of Mississippi, Inc. issued in Mississippi reached the independent review its own staff do not decide, an explicit zero in this insurer's own filed row, not an absence. The stage was there the whole time and it binds the plan. Nationally 22.2% (1,092 of 4,918; interval 22.2-23.8% for counts CMS withheld; 32.6% without SelectHealth) of the reviews that got there were overturned.

Those 93,567 denials are 8.2% of every in-network denial recorded in Mississippi in this release, which makes UnitedHealthcare of Mississippi, Inc. the 2nd largest source of denials of the 2 insurers reporting there. Spread across its 15 plans in the state that is about 6,238 denials per plan. 124 internal appeals were filed against those 93,567 denials. Every one of those denials carried the same two dates the tool at the top of this page works out.

The clock your letter has to describe, in actual dates

Two dates matter more than anything else on this page, and they run the same in Mississippi as everywhere else. You have 180 days from the date on your denial notice to file the internal appeal, and then 4 months from the final internal denial to ask for an independent external review. If waiting would seriously jeopardize your health you can ask for both to be expedited, decided in about 72 hours . Both timeframes are federal, not your insurer's choice, [29 CFR 2560.503-1](https://www.ecfr.gov/current/title-29/section-2560.503-1) ( [PDF](https://www.govinfo.gov/content/pkg/CFR-2024-title29-vol9/pdf/CFR-2024-title29-vol9-sec2560-503-1.pdf) ) and [45 CFR 147.136](https://www.ecfr.gov/current/title-45/section-147.136) ( [PDF](https://www.govinfo.gov/content/pkg/CFR-2024-title45-vol2/pdf/CFR-2024-title45-vol2-sec147-136.pdf) ), in plain English at [HealthCare.gov](https://www.healthcare.gov/appeal-insurance-company-decision/internal-appeals/) , and your own denial letter states the ones that govern your plan. The PDFs are the same sections on govinfo.gov, which serves them without a challenge page, so an automated reader can check these two dates as easily as you can.

Data verified November 4, 2026 · CMS Transparency in Coverage Public Use File (PY2027 release, PY2025 claims), data.healthcare.gov — US Government public domain

You are not alone, and here is the measured version of that sentence: 93,567 in-network claims were denied by UnitedHealthcare of Mississippi, Inc. in Mississippi in a single plan year. A denial rate is a fact about an insurer's book of business. It is not a judgment about you, and it is not the last word on your claim.

- Of the 2 insurers reporting a denial rate in Mississippi, UnitedHealthcare of Mississippi, Inc. is the first highest at 21.7%. The highest in the state is 21.7% and the lowest is 10.7%.

- That is 6 percentage points above the 15.7% national average across this dataset, and 10.5 points above the Mississippi average of 11.2%.

- Behind the percentage: 431,692 in-network claims were processed under 15 plans in Mississippi, and 93,567 of them came back denied.

- For every 10,000 claims UnitedHealthcare of Mississippi, Inc. denied, about 13 came back as an internal appeal. The other 9,987 stopped at the letter.

- Of the internal appeals it did receive, UnitedHealthcare of Mississippi, Inc. overturned 37.1% , 46 claims that started life as a no.

- Not one of those denials reached independent external review, the stage whose decision the plan is required by law to accept, and where nationally 22.2% (1,092 of 4,918; interval 22.2-23.8% for counts CMS withheld; 32.6% without SelectHealth) are overturned.

- Its most-recorded denial reason is other reasons at 34.3% of its categorized denials, against 32.4% nationally, a heavier share than the country as a whole. That is the denial mix, not an outcome rate.

- UnitedHealthcare of Mississippi, Inc. accounts for 8.2% of every in-network claim denied in Mississippi in this file.

- By raw volume it is the 86th largest source of denials among the 135 insurer-state records in the file that report one.

- After that, its second-most-recorded reason is [provider out of network](/denial-reasons/out-of-network) , 37,335 claims, 25.4% of its categorized denials.

- Third on its own list is [member not covered](/denial-reasons/member-not-covered) , 20,284 claims, 13.8% of what UnitedHealthcare of Mississippi, Inc. categorized in Mississippi. Between them the top three account for 73.5% of its categorized denials.

- Where UnitedHealthcare of Mississippi, Inc. differs most from the national mix is [provider out of network](/denial-reasons/out-of-network) : 25.4% of its categorized denials in Mississippi against 9% across the file.

- Read the other way round: 338,125 of those 431,692 in-network claims were paid, 78.3% of everything UnitedHealthcare of Mississippi, Inc. processed in Mississippi.

- Spread across the 15 plans it reports in Mississippi, that is about 6,238 denied claims per plan, on about 28,779 claims processed per plan.

- Its reason columns add up to 147,116 categorized rows against 93,567 denials, 157.2% of them, and every reason share on this page is a share of that first figure rather than of the second.

- Its smallest recorded category in Mississippi is [benefit limit reached](/denial-reasons/benefit-limit-reached) , 45 claims, 0% of what UnitedHealthcare of Mississippi, Inc. categorized there.

- Against the file as a whole, this one record is 0.1% of the 83,907,852 in-network claim denials reported by every issuer in it.

What to do tonight

- Find the reason code on your denial letter. The reason UnitedHealthcare of Mississippi, Inc. records most often in Mississippi is other reasons , but yours may be one of the other 8, copy the exact wording and code off your own letter tonight, because that sentence is what your appeal has to answer.

- Ask UnitedHealthcare of Mississippi, Inc. in Mississippi for the clinical criteria they judged you against. Under [29 CFR 2560.503-1](https://www.ecfr.gov/current/title-29/section-2560.503-1) they have to hand you the claim file and the policy they applied, free, on request, and you cannot argue with a checklist you have never read.

- Put both deadlines on your calendar before you go to bed. 180 days from the date on the letter for the internal appeal, 4 months from the final internal denial for external review. The free calculator on this page turns your date into the two calendar dates in about ten seconds. UnitedHealthcare of Mississippi, Inc. overturned 37.1% of the internal appeals it did receive, 46 claims, so the stage you are about to start is not decorative.

None of those three steps costs anything. Anyone charging you to do them is selling you something you can do yourself in twenty minutes.

21.7%

In-network denial rate

93,567

Claims denied

15

Plans in Mississippi

124

Internal appeals filed

37.1%

Internal overturn rate

## How that compares

| Denial rate | Rate | Difference |
| --- | --- | --- |
| UnitedHealthcare of Mississippi, Inc. | 21.7% | , |
| Mississippi average | 11.2% | +10.5 pts |
| National average (this dataset) | 15.7% | +6 pts |

UnitedHealthcare of Mississippi, Inc. denies 6 percentage points more of its in-network claims than the national average across this dataset. A denial rate is a property of the insurer's book of business, coding practice, plan design, the population it covers, not evidence about the merits of any one claim, including yours.

## What happened to appeals

| Stage | Filed | Overturned |
| --- | --- | --- |
| Internal appeal (to UnitedHealthcare of Mississippi, Inc.) | 124 | 37.1% |
| External review (independent) | 0 | not reported |

Read that again: UnitedHealthcare of Mississippi, Inc. denied 93,567 claims in Mississippi, and not one went to independent external review. External review is free to you and the insurer must follow the decision.

## The gap nobody escalated

93,567 claims denied. 124 internal appeals filed. None reached independent external review. Nationally 22.2% (1,092 of 4,918; interval 22.2-23.8% for counts CMS withheld; 32.6% without SelectHealth) of external reviews are overturned and the decision binds the plan.

That is arithmetic from the reported figures, not a prediction: nobody can say what those specific denials would have done at review, because they never got there. What the numbers do establish is that the binding stage was almost entirely unused here.

What that record means for your own UnitedHealthcare of Mississippi, Inc. letter, and by when. UnitedHealthcare of Mississippi, Inc. overturned 37.1% of the 124 internal appeals its Mississippi members filed against 93,567 denials, and not one of those Mississippi denials went on to the independent stage whose decision binds the plan, UnitedHealthcare of Mississippi, Inc.'s own rows in the plan-year 2027 release of the CMS Transparency in Coverage file, read November 4, 2026 ( [data.healthcare.gov](https://data.healthcare.gov/) ). Whichever way that lands, nobody files the appeal for you, and the filing runs on a clock set by which plan you hold: an employer or Marketplace plan gives you at least 180 days from the denial notice to file the internal appeal ( [29 CFR 2560.503-1(h)(3)(i)](https://www.govinfo.gov/content/pkg/CFR-2024-title29-vol9/pdf/CFR-2024-title29-vol9-sec2560-503-1.pdf) , carried onto individual-market coverage by [45 CFR 147.136(b)(3)(i)](https://www.govinfo.gov/content/pkg/CFR-2024-title45-vol2/pdf/CFR-2024-title45-vol2-sec147-136.pdf) ), while Medicare Advantage gives you 65 calendar days from the date of its notice ( [CMS](https://www.cms.gov/medicare/appeals-grievances/managed-care/reconsideration-advantage-health-plan-part-c) , [42 CFR 422.582(b)](https://www.ecfr.gov/current/title-42/section-422.582) ) and Medicaid managed care 60 calendar days from the date on the notice ( [42 CFR 438.402(c)(2)(ii)](https://www.ecfr.gov/current/title-42/section-438.402) ), both stages free, and the three steps above are the whole of what to do tonight, so take the date printed on your UnitedHealthcare of Mississippi, Inc. notice and file well inside whichever of those windows is yours. The free steps are above; the [$29 kit](/appeal-kit) is the same clock with the letters pre-filled for UnitedHealthcare of Mississippi, Inc. in Mississippi. One payment. No subscription. No cut of your claim.

## UnitedHealthcare of Mississippi, Inc. inside Mississippi

Your denial did not happen in a national average. It happened in a state market, alongside 2 other insurers reporting into the same federal file, and these are that market's own figures.

- Across the whole of Mississippi, the 3 insurers reporting in this file processed 10,238,831 in-network claims and denied 1,141,675 of them, a state denial rate of 11.2%. UnitedHealthcare of Mississippi, Inc. is one of those 3.

- That puts Mississippi 25th of 29 states by denial rate, 4.5 points below the 15.7% national average, before you get to what UnitedHealthcare of Mississippi, Inc. did inside it.

- Mississippi recorded 1,357 internal appeals against those denials: one appeal for every 841 claims the state's insurers refused. UnitedHealthcare of Mississippi, Inc.'s own ratio is one for every 755.

- Not one denial in Mississippi reached independent external review in the reported year, not UnitedHealthcare of Mississippi, Inc.'s and not any other insurer's in the state. That is the stage whose decision the plan is required by law to accept.

- The reason Mississippi's insurers record most often is [other reasons](/denial-reasons/other) , 217,893 claims, 18.9% of the state's categorized denials. UnitedHealthcare of Mississippi, Inc. records the same one most often, so your letter is likely to say it too.

- The other insurers a Mississippi reader could have bought from run from 10.7% ( [Ambetter of Magnolia Inc.](/insurers/ambetter-of-magnolia-inc--ms) ) to 10.7% ( [Ambetter of Magnolia Inc.](/insurers/ambetter-of-magnolia-inc--ms) ). UnitedHealthcare of Mississippi, Inc. at 21.7% sits above all of them.

- Put the two together and UnitedHealthcare of Mississippi, Inc. is responsible for 8.2% of every in-network claim denied in Mississippi in this release, from 4.2% of the claims the state's insurers processed.

- Every Mississippi figure in this section is that state's own row in the same federal file UnitedHealthcare of Mississippi, Inc.'s numbers above come from, [CMS Transparency in Coverage Public Use File (PY2027 release, PY2025 claims), data.healthcare.gov — US Government public domain](https://data.healthcare.gov/) , and the full Mississippi page is free at [/states/mississippi](/states/mississippi) .

## What UnitedHealthcare of Mississippi, Inc. denies most

The most common denial reason recorded for UnitedHealthcare of Mississippi, Inc. plans in Mississippi is other reasons . [How that denial is beaten →](/denial-reasons/other)

| Denial reason | Claims | Share | National share |
| --- | --- | --- | --- |
| Other reasons | 50,518 | 34.3% | 32.4% |
| Provider out of network | 37,335 | 25.4% | 9% |
| Member not covered | 20,284 | 13.8% | 7.9% |
| Administrative reason | 14,108 | 9.6% | 17.2% |
| Referral required | 12,563 | 8.5% | 9.6% |
| Service excluded from the plan | 12,263 | 8.3% | 13.4% |
| Benefit limit reached | 45 | 0% | 4.9% |

The last column is each reason's share of all categorized denials nationally, so you can see where UnitedHealthcare of Mississippi, Inc.'s mix in Mississippi differs from everyone else's. This is denial mix , not overturn rate by reason , the federal file does not report appeal outcomes broken down by denial reason, and we do not imply otherwise.

Work out your two deadlines

Put the date from your notice in and get the two calendar dates, with the days remaining.

Date on your denial notice

Which denial is this?

First denial (I have not appealed yet)

Final internal denial (my appeal was refused)

Show my deadlines

Runs entirely in your browser, the date you type is never sent to us and never stored. [Open the full calculator →](/appeal-deadline-calculator)

Or let the [$29 Appeal Kit](/appeal-kit) date each step and write the claim-file and external-review requests.

The three steps at the top of this page are the whole of what you have to do tonight. The longer
version, what the internal appeal has to contain, how the independent stage works, and how to ask
for expedited handling when waiting would seriously jeopardize your health, is
[published free here](/how-to-appeal) . For what it is worth on this page specifically: UnitedHealthcare of Mississippi, Inc. overturned 37.1% of the internal appeals it received.

## Who appeals what at UnitedHealthcare

UnitedHealthcare runs a mandatory TWO-STEP provider process, a claim reconsideration first, an appeal only after, and is strict about who counts as the member's representative. The first row is the member's route; the others are the provider's. From UnitedHealthcare's published pages, written for health care providers and members; each is listed below with its date. It is brand-level and applies to UnitedHealthcare of Mississippi, Inc. in Mississippi the same as to every other UnitedHealthcare entity in the file.

| Dispute | Route |
| --- | --- |
| A plan denial you want changed (member) | Member, authorized representative or contracted provider. The member form says a timely request; federal rules generally give at least 180 days |
| Post-service claim dispute (provider) | Reconsideration first, then appeal, both steps inside 12 months |
| Pre-service denial | Appeal 'made prior to a planned health care service'; expedited available if delay could seriously jeopardize the member |
| Provider appealing on the member's behalf | Requires authorization/patient consent, an assignment of benefits is NOT enough |

##### Operational facts from the same policy

- Combined window for both steps: 12 months , One clock covers both steps — a slow reconsideration eats the appeal window.

- Two-step structure is mandatory: reconsideration, then appeal

- Assignment of benefits is not representation: separate patient consent needed , For patients: your provider billing UnitedHealthcare for you does NOT automatically let them appeal AS you — a separate authorization is needed, or you appeal yourself.

- Submission is portal/API: UnitedHealthcare Provider Portal or API , No mailing address or fax is published on this page.

- Expedited appeal is pre-service only: not available after the service

- Peer-to-peer review windows: 3 business days inpatient / 21 calendar days outpatient

- Member grievance window (California section of the form): 180 calendar days , Member-side second source. This wording sits under the form's California grievance instructions, so it is not a national appeal deadline. UnitedHealthcare's provider page publishes no member window.

- Who may appeal (member side): member, authorized representative, or contracted provider

- Member review clocks: acknowledge 5 days, decide 30 days standard / 3 days urgent , Stated on a form page that also carries California-specific sections (DMHC 1-888-466-2219, Independent Medical Review) — plan-state specifics can vary.

Sources: [UnitedHealthcare, "Pre- and post-service appeals and reconsiderations"](https://www.uhcprovider.com/en/claims-payments-billing/appeals.html) , quoted, not paraphrased; audience: health care providers; checked 2026-11-05. [UnitedHealthcare, "Member service request form (memberforms.uhc.com — carries state-specific sections incl. California IMR; undated)"](https://memberforms.uhc.com/Memberappealsandgrievances.html) , quoted, not paraphrased; audience: members; checked 2026-11-05. Brand-level policy, applied here because UnitedHealthcare of Mississippi, Inc. is a UnitedHealthcare entity. Your own denial letter and plan documents govern your specific case.

## Questions

##### Is UnitedHealthcare of Mississippi, Inc.'s denial rate in Mississippi high?

21.7% against a national average of 15.7% across the plans in this dataset. It is above average. A denial rate describes the insurer, not the merits of your claim.

##### How many people appealed a UnitedHealthcare of Mississippi, Inc. denial in Mississippi, and how many won?

124 internal appeals were filed against 93,567 denials, and 37.1% of them were overturned (46 claims). Not one went on to independent external review, the stage whose decision is binding on the plan.

##### How does UnitedHealthcare of Mississippi, Inc. compare with other insurers in Mississippi?

Of the 2 insurers in Mississippi with a reported denial rate, UnitedHealthcare of Mississippi, Inc. ranks 1 highest at 21.7%. The highest in Mississippi is UnitedHealthcare of Mississippi, Inc. at 21.7%; the lowest is Ambetter of Magnolia Inc. at 10.7%.

##### What does UnitedHealthcare of Mississippi, Inc. deny most often in Mississippi?

Other reasons, 50,518 claims, 34.3% of this issuer's categorized denials, against 32.4% nationally. This is the denial-reason mix; the federal file does not report overturn rates by reason.

##### How long do I have to appeal a UnitedHealthcare of Mississippi, Inc. denial in Mississippi?

Generally 180 days from the date on the denial notice to file the internal appeal, then generally four months from the final internal denial to request independent external review. Expedited review, decided in about 72 hours, is available where delay would seriously jeopardize your health. Those timeframes are federal, so they are identical for every insurer reporting in Mississippi, UnitedHealthcare of Mississippi, Inc. included, what varies by state is who runs the independent review at the end. Your own denial letter states the deadlines that govern your plan; that letter is the authority.

##### Does appealing a UnitedHealthcare of Mississippi, Inc. denial in Mississippi cost anything?

The internal appeal to UnitedHealthcare of Mississippi, Inc. is free. External review is free under the HHS-administered federal process; where an issuer uses a contracted independent review organization or a state process, any fee is capped at $25 per review. Nobody in Mississippi can be charged more than that to file one.

##### Can UnitedHealthcare of Mississippi, Inc. ignore an external review decision in Mississippi?

No, and that is the whole point of the stage. External review decisions are binding on the plan by law, which is what makes the zero external reviews recorded against 93,567 UnitedHealthcare of Mississippi, Inc. denials in Mississippi the striking number on this page.

The line on this page we would read twice is the one that says not one of UnitedHealthcare of Mississippi, Inc.'s 93,567 denials in Mississippi reached independent review. We are not going to tell you that you will win. This page prints the insurer's own reported numbers whichever way they fall. If what it says does not match the letter in your hand, write to us and we will correct the page.

Axion Labs · hello@getaxionlabs.com

[Get my Appeal Kit, $29](/appeal-kit)
Everything you need for your UnitedHealthcare of Mississippi, Inc. appeal in Mississippi: your two deadlines, the argument that fits your denial reason, the letters, a brief for your doctor on what the reviewer checks, and the external review request. One payment. No subscription. No cut of your claim. Opens on screen the moment you pay. 14-day refund, no questions, one email to hello@getaxionlabs.com.

Where these numbers come from The UnitedHealthcare of Mississippi, Inc. figures on this page, the 21.7% denial rate, the 93,567 denials and the 0 external reviews, are this issuer’s own reported rows in that file.

Counts: [CMS Transparency in Coverage Public Use File (PY2027 release, PY2025 claims), data.healthcare.gov — US Government public domain](https://data.healthcare.gov/) . Rights and timeframes: [29 CFR 2560.503-1](https://www.ecfr.gov/current/title-29/section-2560.503-1) (180 days, and your free right to the claim file) and [45 CFR 147.136](https://www.ecfr.gov/current/title-45/section-147.136) (4 months, and what qualifies), explained at [HealthCare.gov](https://www.healthcare.gov/appeal-insurance-company-decision/external-review/) . Expedited review is decided in about 72 hours under both sections.

Reading either regulation from a script rather than a browser: eCFR answers automated fetches with a challenge page, so the same two sections are mirrored as government PDFs at [govinfo.gov (29 CFR 2560.503-1)](https://www.govinfo.gov/content/pkg/CFR-2024-title29-vol9/pdf/CFR-2024-title29-vol9-sec2560-503-1.pdf) and [govinfo.gov (45 CFR 147.136)](https://www.govinfo.gov/content/pkg/CFR-2024-title45-vol2/pdf/CFR-2024-title45-vol2-sec147-136.pdf) .

This page presents federal statistics and a general description of appeal rights created by federal law. It is not legal, medical, or insurance advice, and no outcome is guaranteed. Your denial letter and plan documents govern your specific case. Free help is available from your state's Consumer Assistance Program and from the federal Marketplace at HealthCare.gov.

Problem solved: You have both dates for your UnitedHealthcare of Mississippi, Inc. notice, you know that Mississippi runs the external review itself, and you have the letter, free, on this screen, tonight.

## The pages that answer the next question

- [Every insurer reporting in Mississippi](/states/mississippi) , the state's own row, the 3 companies filing there, and the Mississippi insurance department's consumer number, read at source.

- [United Healthcare denial rate](/company/unitedhealthcare) , UnitedHealthcare of Mississippi, Inc. is the Mississippi one; the brand's national rate is 20.4% across 38,271,926 claims in 19 states, and it is not the same in any two of them.

- [If United Healthcare denied your claim](/united-healthcare-denying-claims) , UnitedHealthcare's own appeal steps, quoted and labeled member or provider, and the two federal dates for your notice. This record is the Mississippi one.

- [UnitedHealthcare of North Carolina, Inc in North Carolina](/insurers/unitedhealthcare-of-north-carolina-inc--nc) , 22.4% of in-network claims denied, 363,243 of them, the neighboring record in this file.

- [UnitedHealthcare of Ohio, Inc. in Ohio](/insurers/unitedhealthcare-of-ohio-inc--oh) , 23.9% of in-network claims denied, 185,791 of them, the neighboring record in this file.

- [UnitedHealthcare of Oklahoma, Inc. in Oklahoma](/insurers/unitedhealthcare-of-oklahoma-inc--ok) , 25.4% of in-network claims denied, 65,121 of them, the neighboring record in this file.

- [If your employer pays the claims itself](/self-funded-denial) , then UnitedHealthcare of Mississippi, Inc. is only administering the plan, your state's external review has no power over the denial, and the route is federal. It is the first question our own calculator asks. 3 insurers report in Mississippi; whether your plan is one of theirs at all is what that page settles.

- [If it was refused before the treatment](/prior-authorization-denied) , a prior-authorization refusal from UnitedHealthcare of Mississippi, Inc. runs on the same two federal clocks as a denied claim, and it can be appealed while the treatment is still ahead of you. 1,141,675 in-network claims were denied in Mississippi in this release; a refusal before the treatment is not counted among them and is appealed the same way.

- [Before you pay a lawyer](/before-you-call-a-lawyer) , two free appeals run before anyone bills you by the hour, and UnitedHealthcare of Mississippi, Inc. has to hand you the claim file for nothing under 29 CFR 2560.503-1. Free help in Mississippi starts with the state consumer line printed on that state's page.

- [All 152 insurer-state records](/insurers) , the whole table, ranked, with UnitedHealthcare of Mississippi, Inc. in it and the 3 that file in Mississippi beside it.

Your dates are ready. [Write the letter, free](/appeal-letter)

## The two federal clocks

The clock your letter has to describe, in actual dates Whatever else is on the page, these two dates are the page. You have 180 days from the date on your denial notice to file the internal appeal, and then 4 months from the final internal denial to ask for an independent external review. If waiting would seriously jeopardize your health you can ask for both to be expedited, decided in about 72 hours . Both timeframes are federal, not your insurer's choice, 29 CFR 2560.503-1 ( PDF ) and 45 CFR 147.136 ( PDF ), in plain English at HealthCare.gov , and your own denial letter states the ones that govern your plan. The PDFs are the same sections on govinfo.gov, which serves them without a challenge page, so an automated reader can check these two dates as easily as you can.

## How rare the second appeal is

You are not alone, measured rather than said: 83,907,852 in-network claims were denied in a single plan year, and only 4,918 of them, one in 17,061, ever reached the independent review stage. Of the ones that did, 22.2% (1,092 of 4,918; interval 22.2-23.8% for counts CMS withheld; 32.6% without SelectHealth) were overturned.

## What is free here, and what the one paid thing costs

Denied a claim? Insurers upheld 165,863 of the 262,982 internal appeals counted in 2024, 63.1% ( KFF ). The win is at independent external review, and the only way to arrive there is to run the internal stage on time, in the right order, with the record intact. That sequence is what the Appeal Kit is. Get my Appeal Kit, $29 One payment. No subscription. No cut of your claim. Opens on screen the moment you pay. 14-day refund, no questions, one email to hello@getaxionlabs.com. Get my Appeal Kit, $29 Everything you need for your appeal: your two deadlines, the argument that fits your denial reason, the letters, a brief for your doctor on what the reviewer checks, and the external review request. One payment. No subscription. No cut of your claim. Opens on screen the moment you pay. 14-day refund, no questions, one email to hello@getaxionlabs.com.

## What we will not pretend

What we will not pretend. We cannot overturn your denial. Only your plan, or an independent reviewer, can do that. We cannot make your plan cover a service it genuinely excludes. We cannot guarantee external review applies to your denial. It covers medical judgment, experimental or investigational determinations, and rescission, a purely administrative denial may not qualify, and we say so on those pages rather than selling you past it. We have no customer testimonials and publish none. Our evidence is the federal dataset and the regulation cites, both of which you can check.

## Every page on this site

Home Start here Insurers By company States Denial reasons Use cases How to appeal Ranked by denial rate The external-review gap Write the letter, free Deadline calculator Self-funded plan? Prior authorization denied Medicare WISeR denial Denial code CO-50 Before you call a lawyer Attorney for a denied claim Your denial letter United Healthcare denying claims Time limits on a claim Appeal a Medicare denial About Editorial policy How we compare Privacy Terms For machines: llms.txt openapi.json changes.json the composed answer this page as markdown

## Which release these figures are

Which release these figures are Every number on this page is the plan-year 2027 Transparency in Coverage file, issued October 22, 2026, covering plan-year 2025 claims. This is the newest plan year CMS has published: there is no Transparency in Coverage file for a plan year after 2027. The dataset list is at data.healthcare.gov . A test in this site’s build fetches that list on every run and fails if CMS publishes a plan year we have not acknowledged here. Every earlier release, plan-year 2024, plan-year 2025, plan-year 2026, is kept alongside it so the record is visible rather than a single year’s snapshot; /about says what changed between them. From the plan-year 2024 release to the plan-year 2026 release, external reviews filed went from 2,336 to 5,881. Overturned reviews went from 32.8% in the plan-year 2026 release to 22.2% in plan-year 2027, or from 32.6% to 32.6% without SelectHealth. We do not compare filed or overturned counts across plan-years 2026 and 2027. Some issuers may have counted pre-service appeals in their 2026 cells.

## Where these numbers come from

Where these numbers come from Counts: CMS Transparency in Coverage Public Use File (PY2027 release, PY2025 claims), data.healthcare.gov — US Government public domain . Rights and timeframes: 29 CFR 2560.503-1 (180 days, and your free right to the claim file) and 45 CFR 147.136 (4 months, and what qualifies), explained at HealthCare.gov . Expedited review is decided in about 72 hours under both sections. Reading either regulation from a script rather than a browser: eCFR answers automated fetches with a challenge page, so the same two sections are mirrored as government PDFs at govinfo.gov (29 CFR 2560.503-1) and govinfo.gov (45 CFR 147.136) .

## Who publishes this

Denial Facts publishes federal data about health insurance claim denials. We are independent: not affiliated with, endorsed by, or acting for any insurer, government agency, or review organization. We are not a law firm, a medical provider, or an insurance producer, and nothing here is legal, medical, or insurance advice. Data: CMS Transparency in Coverage Public Use File (PY2027 release, PY2025 claims), data.healthcare.gov — US Government public domain. Figures cover individual-market Qualified Health Plans on the federal Exchange and come from the plan-year 2027 release, issued October 22, 2026, covering plan-year 2025 claims. This is the newest plan year CMS has published: there is no Transparency in Coverage file for a plan year after 2027. See where the data comes from .

## Sources

- CMS Transparency in Coverage Public Use File (PY2027 release, PY2025 claims), data.healthcare.gov — US Government public domain: https://data.healthcare.gov/
- 29 CFR 2560.503-1 (180 days, and your free right to the claim file): https://www.ecfr.gov/current/title-29/section-2560.503-1
- 45 CFR 147.136 (4 months, and what qualifies): https://www.ecfr.gov/current/title-45/section-147.136
- HealthCare.gov on external review: https://www.healthcare.gov/appeal-insurance-company-decision/external-review/

Cite: Axion Labs — Denial Facts, "UnitedHealthcare of Mississippi appeal form and deadline", https://denialfacts.com/insurers/unitedhealthcare-of-mississippi-inc--ms (checked 2026-11-04). free to quote with the URL.