What percentage of denied health insurance claims are appealed?

Fewer than 1%. In the CMS filings for 2024, HealthCare.gov members filed 263,142 internal appeals against 83,276,964 in-network denials: 3.16 per 1,000 (0.32%). KFF's analysis of the same file reports an appeal rate below 1%.

How often do appeals succeed when they are filed?

32.6% of internal appeals in the 2024 filings were decided for the member. Among issuers with at least 100 appeals, the overturn rate runs from 0.0% to 85.7%. External reviews were requested 5,881 times and reversed the insurer in 32.8% of them.

For organizations Start my appeal

Research · CMS PY2026 file · 2024 claims · Updated 2026-09-14

The appeal participation gap: 3.2 appeals for every 1,000 denials

Insurers denied 83,276,964 in-network claims in 2024 across 148 HealthCare.gov issuer filings. Members appealed 263,142 of them. Where they did appeal, 32.6% won. The gap between those two numbers is the largest unclaimed money in American health insurance, and it is not evenly distributed.

3.2

appeals filed per 1,000 in-network denials, all issuers pooled

263,142 appeals against 83,276,964 denials (0.32%)

32.6%

of internal appeals decided in the member's favour

same filings, pooled

32.8%

of the 5,881 external reviews reversed the insurer

independent review organizations, same filings

Insurers whose members appeal most and least

Appeals per 1,000 denials. A high number can mean an engaged membership, an insurer that makes appealing easy, or a denial mix that invites challenge; a very low number, especially on a large denial count, is the population to reach first.

Most appealed	Per 1,000	Denials	Won
PacificSource Health Plans (OR)	206.7	658	8.8%
Oscar Insurance Company (NE)	93.3	10,186	46.0%
Oscar Insurance Company (OK)	70.2	60,135	27.4%
CHRISTUS Health Plan Louisiana (LA)	69.3	22,585	40.9%
Oscar Insurance Corporation of Ohio (OH)	67.2	121,739	34.1%
Anthem Health Plans of NH(Anthem BCBS) (NH)	62.6	2,555	44.4%
Oscar Insurance Company (IA)	62.0	117,430	29.8%
Kaiser Foundation Health Plan, Inc. (HI)	56.5	584	48.5%
Oscar Buckeye State Insurance Corp. (OH)	55.4	337,922	25.1%
Oscar Health Plan, Inc. (AZ)	53.9	82,246	20.7%

Least appealed (10,000+ denials)	Per 1,000	Denials	Won
Common Ground Healthcare Cooperative (WI)	0.0	143,772	0.0%
Sendero Health Plans, Inc. (TX)	0.2	101,311	66.7%
AvMed, Inc. (FL)	0.2	118,089	n/a
Celtic Insurance Company (NH)	0.2	133,926	58.1%
Molina Healthcare of Florida, Inc (FL)	0.2	341,296	23.2%
Highmark Blue Cross Blue Shield West Virginia (WV)	0.3	471,125	31.5%
Health Options, Inc. (FL)	0.3	10,507,969	44.8%
Blue Care Network of Michigan (MI)	0.3	630,298	85.7%
Cigna Health and Life Insurance Company (MS)	0.4	691,183	48.6%
Aspirus Health Plan, Inc. (WI)	0.4	47,925	n/a

Where appeals win, and where they almost never do

Issuer filings with at least 100 internal appeals. An overturn rate near zero on hundreds or thousands of appeals is worth a regulator's question; it is also the case for going straight to external review.

Highest overturn rate	Won	Appeals
Blue Care Network of Michigan (MI)	85.7%	210
Summa Insurance Company, Inc. (OH)	76.8%	319
Providence Health Plan (OR)	72.1%	301
Sanford Health Plan (ND)	65.3%	147
Security Health Plan of Wisconsin, Inc. (WI)	65.1%	258
Medical Health Insuring Corp. of Ohio (OH)	64.1%	657
Medica Insurance Company (OK)	63.9%	144
Cigna HealthCare of Texas, Inc. (TX)	63.8%	1,184
Health First Commercial Plans, Inc. (FL)	63.3%	403
Celtic Insurance Company (TX)	61.2%	3,010

Lowest overturn rate	Won	Appeals
Ambetter of Magnolia Inc. (MS)	0.0%	1,147
Celtic Insurance Company (AR)	0.0%	1,813
QCA Health Plan, Inc. (AR)	0.0%	346
QualChoice Life & Health Insurance Company, Inc. (AR)	0.0%	397
Celtic Insurance Company (KS)	1.8%	1,121
Health Net of Arizona, Inc. (AZ)	2.8%	502
CareSource West Virginia Co. (WV)	6.6%	993
PacificSource Health Plans (OR)	8.8%	136
Regence BlueCross BlueShield of Utah (UT)	12.3%	487
CareSource North Carolina Co. (NC)	13.1%	728

Every issuer filing

Issuer	State	Denials	Appeals	Per 1,000	Won	External reviews	Reversed
PacificSource Health Plans	OR	658	136	206.69	8.8%	n/a	n/a
Oscar Insurance Company	NE	10,186	950	93.27	46.0%	16	n/a
Oscar Insurance Company	OK	60,135	4,223	70.23	27.4%	83	43.4%
CHRISTUS Health Plan Louisiana	LA	22,585	1,566	69.34	40.9%	0	0.0%
Oscar Insurance Corporation of Ohio	OH	121,739	8,186	67.24	34.1%	255	26.3%
Anthem Health Plans of NH(Anthem BCBS)	NH	2,555	160	62.62	44.4%	n/a	n/a
Oscar Insurance Company	IA	117,430	7,284	62.03	29.8%	144	27.8%
Kaiser Foundation Health Plan, Inc.	HI	584	33	56.51	48.5%	0	0.0%
Oscar Buckeye State Insurance Corp.	OH	337,922	18,709	55.36	25.1%	394	25.6%
Oscar Health Plan, Inc.	AZ	82,246	4,434	53.91	20.7%	152	32.9%
Kaiser Foundation Healthplan of the NW	OR	725	39	53.79	43.6%	0	0.0%
Oscar Insurance Company	KS	77,239	4,096	53.03	35.2%	80	18.8%
Oscar Insurance Company	TN	187,709	9,553	50.89	38.3%	162	18.5%
Oscar Insurance Company	TX	764,285	38,325	50.14	23.6%	517	34.0%
Oscar Health Plan of North Carolina, Inc	NC	17,549	875	49.86	36.6%	34	35.3%
Oscar Insurance Company	MO	133,294	5,920	44.41	31.8%	53	24.5%
Oscar Insurance Company	MI	14,778	596	40.33	30.7%	46	23.9%
CHRISTUS Health Plan	TX	141,176	4,256	30.15	31.4%	0	0.0%
Blue Cross and Blue Shield of Arizona, Inc.	AZ	233,016	4,769	20.47	37.9%	180	20.0%
Providence Health Plan	OR	16,582	301	18.15	72.1%	n/a	n/a
CareSource North Carolina Co.	NC	44,782	728	16.26	13.1%	n/a	n/a
Avera Health Plans, Inc.	SD	11,752	154	13.10	44.8%	n/a	n/a
Montana Health Cooperative	MT	91,410	1,163	12.72	24.0%	16	n/a
USAble Mutual Insurance Company	AR	669,702	7,600	11.35	31.6%	35	37.1%
Sanford Health Plan	SD	35,230	365	10.36	59.7%	n/a	n/a
Blue Cross and Blue Shield of Nebraska	NE	91,925	870	9.46	22.8%	17	n/a
CareSource Ohio, Inc.	OH	562,546	5,001	8.89	19.0%	263	17.9%
CareSource Indiana, Inc.	IN	638,511	5,621	8.80	16.6%	436	25.5%
Regence BlueCross BlueShield of Utah	UT	58,383	487	8.34	12.3%	11	n/a
Capital Health Plan	FL	35,255	257	7.29	33.9%	n/a	n/a
Summa Insurance Company, Inc.	OH	51,591	319	6.18	76.8%	n/a	n/a
Regence BlueCross BlueShield of Oregon	OR	100,498	616	6.13	14.3%	47	n/a
USAble HMO, Inc.	AR	123,118	686	5.57	32.1%	0	0.0%
UnitedHealthcare Insurance Company	MO	203,531	1,119	5.50	34.5%	n/a	n/a
UnitedHealthcare Insurance Company	KS	167,716	915	5.46	31.5%	n/a	n/a
UnitedHealthcare of Wisconsin, Inc.	WI	113,541	594	5.23	41.1%	n/a	n/a
Sanford Health Plan	ND	28,533	147	5.15	65.3%	n/a	n/a
HMO Partners, Inc.	AR	248,827	1,247	5.01	29.1%	n/a	n/a
CareSource West Virginia Co.	WV	198,752	993	5.00	6.6%	54	31.5%
UnitedHealthcare of Texas, Inc.	TX	2,550,560	12,386	4.86	35.0%	67	31.3%
UnitedHealthcare of Florida, Inc.	FL	719,832	3,373	4.69	26.2%	18	n/a
UnitedHealthcare of South Carolina, Inc.	SC	88,229	403	4.57	31.0%	n/a	n/a
UnitedHealthcare of Ohio, Inc.	OH	208,089	944	4.54	35.0%	21	n/a
Anthem Ins Companies Inc(Anthem BCBS)	IN	267,110	1,174	4.40	30.6%	n/a	n/a
Scott and White Health Plan	TX	1,205,777	5,246	4.35	60.2%	170	80.0%
Molina Healthcare of Texas, Inc.	TX	237,126	996	4.20	54.7%	21	66.7%
UnitedHealthcare of North Carolina, Inc	NC	339,054	1,407	4.15	37.4%	n/a	n/a
UnitedHealthcare of Arizona, Inc.	AZ	646,181	2,607	4.03	38.1%	33	n/a
University of Utah Health Insurance Plans	UT	122,297	482	3.94	32.2%	n/a	n/a
UnitedHealthcare of Oklahoma, Inc.	OK	59,525	218	3.66	19.7%	0	0.0%
Quartz Health Benefit Plans Corporation	WI	57,350	204	3.56	48.0%	n/a	n/a
SelectHealth, Inc.	UT	1,571,221	5,422	3.45	27.1%	119	44.5%
UnitedHealthcare Insurance Company	TN	446,509	1,483	3.32	31.7%	n/a	n/a
Medical Health Insuring Corp. of Ohio	OH	198,720	657	3.31	64.1%	21	n/a
UnitedHealthcare Community Plan, Inc.	MI	204,912	671	3.27	23.7%	0	0.0%
Blue Cross Blue Shield of Oklahoma	OK	1,385,537	4,404	3.18	29.6%	50	44.0%
UnitedHealthcare of Mississippi, Inc.	MS	67,514	196	2.90	31.1%	0	0.0%
Blue Cross and Blue Shield of Kansas City	MO	31,697	91	2.87	33.0%	0	0.0%
Community Insurance Company(Anthem BCBS)	OH	294,314	841	2.86	26.8%	n/a	n/a
CommunityCare HMO Inc.	OK	74,500	204	2.74	50.5%	n/a	n/a
Molina Healthcare of Utah	UT	28,618	78	2.73	71.8%	0	0.0%
Medica Health Plans	ND	15,098	40	2.65	37.5%	0	0.0%
Medica Community Health Plan	WI	87,505	227	2.59	54.6%	0	0.0%
Matthew Thornton Hlth Plan(Anthem BCBS)	NH	153,654	396	2.58	41.9%	0	0.0%
Medica Insurance Company	NE	281,819	720	2.55	49.3%	11	n/a
UnitedHealthcare Insurance Company	AL	1,073,259	2,741	2.55	38.5%	n/a	n/a
Blue Cross and Blue Shield of Alabama	AL	2,038,603	5,200	2.55	50.1%	13	0.0%
Harvard Pilgrim Health Care of NE	NH	33,754	84	2.49	33.3%	0	0.0%
Louisiana Health Service & Indemnity Company	LA	147,920	364	2.46	32.1%	41	n/a
Dean Health Plan	WI	160,914	391	2.43	49.4%	0	0.0%
Blue Cross and Blue Shield of Montana	MT	142,689	336	2.35	30.9%	16	n/a
Wellmark of South Dakota	SD	65,429	152	2.32	28.3%	n/a	n/a
Medica Insurance Company	MO	95,180	208	2.19	48.1%	0	0.0%
Medica Insurance Company	IA	89,569	195	2.18	50.3%	n/a	n/a
Blue Cross and Blue Shield of Kansas City	KS	20,939	44	2.10	38.6%	0	0.0%
UnitedHealthcare Insurance Company	LA	248,739	521	2.09	34.9%	n/a	n/a
Blue Cross Blue Shield of Texas	TX	11,028,737	22,641	2.05	50.3%	808	40.2%
Medica Insurance Company	KS	14,017	27	1.93	44.4%	n/a	n/a
Paramount Insurance Company	OH	15,746	30	1.91	73.3%	0	0.0%
Blue Cross Blue Shield of Wyoming	WY	229,909	434	1.89	39.9%	n/a	n/a
MOLINA HEALTHCARE OF SOUTH CAROLINA, INC	SC	230,150	422	1.83	57.6%	0	0.0%
HMO Louisiana, Inc.	LA	993,016	1,813	1.83	33.2%	247	22.7%
Blue Cross Blue Shield of North Dakota	ND	96,964	177	1.83	44.6%	0	0.0%
Cigna HealthCare of Arizona, Inc	AZ	22,637	39	1.72	56.4%	n/a	n/a
Sunshine State Health Plan	FL	256,694	437	1.70	n/a	n/a	n/a
Florida Health Care Plan, Inc.	FL	602,771	1,024	1.70	27.4%	36	52.8%
Cox Health Systems Insurance Company	MO	14,549	24	1.65	45.8%	0	0.0%
Compcare Health Serv Ins Co(Anthem BCBS)	WI	213,637	344	1.61	58.4%	n/a	n/a
Blue Cross and Blue Shield of South Carolina	SC	1,827,005	2,902	1.59	41.9%	234	56.4%
Celtic Insurance Company	TN	1,645,943	2,600	1.58	n/a	n/a	n/a
Celtic Insurance Company	KS	734,165	1,121	1.53	1.8%	17	0.0%
QualChoice Life & Health Insurance Company, Inc.	AR	262,731	397	1.51	0.0%	0	0.0%
Medica Central Insurance Company	MO	13,403	20	1.49	n/a	0	0.0%
QCA Health Plan, Inc.	AR	245,717	346	1.41	0.0%	0	0.0%
Celtic Insurance Company	AR	1,297,980	1,813	1.40	0.0%	0	0.0%
Medica Insurance Company	OK	103,679	144	1.39	63.9%	0	0.0%
Ambetter of North Carolina Inc.	NC	924,286	1,238	1.34	n/a	n/a	n/a
Cigna HealthCare of Texas, Inc.	TX	884,055	1,184	1.34	63.8%	n/a	n/a
Cigna Health and Life Insurance Company	FL	926,080	1,210	1.31	32.1%	15	n/a
Blue Cross and Blue Shield of Kansas, Inc.	KS	134,229	174	1.30	55.2%	12	n/a
Moda Health Plan, Inc.	AK	29,231	35	1.20	48.6%	0	0.0%
Celtic Insurance Company	TX	2,652,607	3,010	1.13	61.2%	237	54.9%
Moda Health Plan, Inc.	TX	34,484	39	1.13	35.9%	n/a	n/a
Moda Health Plan, Inc.	OR	157,741	173	1.10	38.7%	n/a	n/a
Celtic Insurance Company	AL	352,236	377	1.07	n/a	n/a	n/a
Security Health Plan of Wisconsin, Inc.	WI	247,191	258	1.04	65.1%	0	0.0%
Celtic Insurance Company	OK	438,378	446	1.02	n/a	n/a	n/a
Wellmark Health Plan of Iowa, Inc.	IA	704,036	674	0.96	32.8%	n/a	n/a
Cigna HealthCare of North Carolina, Inc.	NC	162,599	150	0.92	26.0%	n/a	n/a
Healthy Alliance Life Co(Anthem BCBS)	MO	295,802	270	0.91	36.3%	0	0.0%
Meridian Health Plan of Michigan, Inc.	MI	941,541	844	0.90	n/a	n/a	n/a
Cigna Health and Life Insurance Company	IN	75,221	67	0.89	49.3%	n/a	n/a
Premera Blue Cross Blue Shield of Alaska	AK	210,082	187	0.89	47.6%	n/a	n/a
Ambetter Health of Louisiana, Inc.	LA	326,106	289	0.89	n/a	n/a	n/a
Absolute Total Care, Inc	SC	1,471,467	1,299	0.88	n/a	n/a	n/a
Blue Cross Blue Shield of Michigan Mutual Insurance Company	MI	236,257	203	0.86	46.8%	78	n/a
McLaren Health Plan Community	MI	19,916	17	0.85	88.2%	0	0.0%
Health First Commercial Plans, Inc.	FL	475,722	403	0.85	63.3%	37	n/a
Health Net of Arizona, Inc.	AZ	596,289	502	0.84	2.8%	n/a	n/a
Superior Health Plan	TX	1,287,305	1,083	0.84	57.4%	62	50.0%
MercyCare HMO, Inc.	WI	19,105	15	0.79	n/a	0	0.0%
Cigna Health and Life Insurance Company	TN	955,423	720	0.75	52.8%	n/a	n/a
Select Health of South Carolina	SC	39,520	29	0.73	55.2%	0	0.0%
Community Health Choice, Inc.	TX	1,449,319	1,054	0.73	24.7%	26	61.5%
Blue Cross and Blue Shield of Florida	FL	4,251,990	3,012	0.71	47.6%	170	45.9%
Blue Cross and Blue Shield of NC	NC	3,116,071	2,160	0.69	36.1%	88	50.0%
AmeriHealth Caritas North Carolina, Inc.	NC	109,227	74	0.68	63.5%	0	0.0%
AmeriHealth Caritas VIP Next, Inc.	DE	46,346	31	0.67	45.2%	0	0.0%
Network Health Plan	WI	48,655	31	0.64	38.7%	0	0.0%
Ambetter of Magnolia Inc.	MS	1,824,195	1,147	0.63	0.0%	0	0.0%
Molina Healthcare of Mississippi, Inc	MS	142,847	87	0.61	62.1%	0	0.0%
Highmark BCBSD Inc.	DE	387,306	222	0.57	30.6%	n/a	n/a
Hawaii Medical Service Association	HI	198,069	104	0.53	50.0%	0	0.0%
Molina Healthcare of Ohio, Inc.	OH	428,806	216	0.50	50.0%	n/a	n/a
Buckeye Community Health Plan	OH	714,834	333	0.47	59.5%	n/a	n/a
BlueCross BlueShield of Tennessee	TN	1,323,501	587	0.44	45.0%	n/a	n/a
Priority Health	MI	324,164	130	0.40	21.5%	n/a	n/a
Aspirus Health Plan, Inc.	WI	47,925	19	0.40	n/a	n/a	n/a
Cigna Health and Life Insurance Company	MS	691,183	257	0.37	48.6%	n/a	n/a
Blue Care Network of Michigan	MI	630,298	210	0.33	85.7%	65	n/a
Health Options, Inc.	FL	10,507,969	3,129	0.30	44.8%	153	50.3%
Highmark Blue Cross Blue Shield West Virginia	WV	471,125	130	0.28	31.5%	n/a	n/a
Molina Healthcare of Florida, Inc	FL	341,296	82	0.24	23.2%	0	0.0%
Celtic Insurance Company	NH	133,926	31	0.23	58.1%	n/a	n/a
AvMed, Inc.	FL	118,089	25	0.21	n/a	0	0.0%
Sendero Health Plans, Inc.	TX	101,311	21	0.21	66.7%	n/a	n/a
Taro Health Plan of Oklahoma, Inc.	OK	642	0	0.00	0.0%	0	0.0%
Common Ground Healthcare Cooperative	WI	143,772	0	0.00	0.0%	0	0.0%

Method

Source: CMS Transparency in Coverage public use files. Issuer-level, self-reported, HealthCare.gov plans only; a denial includes duplicate, administrative and eligibility denials. Filings with fewer than 1,000 in-network claims are excluded from rankings. Appeals are internal appeals filed with the issuer as reported in the file; the file does not say how many were medical-necessity denials versus administrative ones. Per-1,000 rates use the issuer's own denial count as the denominator. External review counts are as reported by the issuer. Comparison point: KFF, Claims Denials and Appeals in ACA Marketplace Plans in 2024 (24 March 2026) reports at least 262,982 appeals against about 85 million denials in the same file; Apellica's pooled figure differs slightly because dental issuers and filings under 1,000 claims are excluded here.

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Apellica (2026). The appeal participation gap. https://apellica.com/research/appeal-participation-gap-2026

Corrections: editorial@apellica.com · Press: press@apellica.com · Nothing here predicts an individual claim; it describes populations.

General information, not legal or medical advice. Apellica is an appeal-preparation service, not a law firm.