New data reveals which health insurers deny the most claims from poor people

One-fifth of insurance claims from Americans relying on Obamacare were rejected last year, denying access to care for millions of people.

An analysis from health policy charity Kaiser Family Foundation (KFF) evaluated nearly 400million claims made to insurance companies included in the Affordable Care Act (ACA), which provides insurance to 21million lower-income Americans. 

The researchers found about 19 percent of claims for in-network services - from a provider who works with that insurance - were denied in 2023, a 15 percent jump from the year before. 

The rate was even more staggering for out-of-network coverage, with nearly four in 10 claims being denied.

The team also found Blue Cross Blue Shield of Alabama, which serves 3million residents, denied 35 percent of claims, the most of any insurance company included in the ACA, also called ObamaCare.

UnitedHealth Group, which has come under fire over accusations of halting lifesaving medical care and overcharging patients, came in close second, refusing one in three claims filed in 2023 in for its ACA plans in 20 states.

And Health Care Service Corporation, America's fifth-largest health insurer, denied 29 percent of claims. 

While GuideWell Mutual Holding, a subsidiary of Blue Cross Blue Shield of Florida, shot down the fewest claims, it was still responsible for one in eight denials.

The most common reason claims were denied was listed as 'other,' meaning there was no clear explanation. This was the reason listed for one in three denied claims.

'Administrative reason,' excluded services, and enrollees reaching their maximum coverage limit were among the most common reasons for denied claims.

However, the researchers noted details were sparse, so there were no explanations provided.  

Treatments being deemed 'not medically necessary' made up one in 20 denied claims. It's unclear what the treatments were for. 

Despite the high rates of denials, the analysis found fewer than one in 100 patients appealed their claims. 

However, in the rare instances they did, insurance companies upheld their decisions more than half of the time. 

It's unclear how much patients had to pay for denied claims.  

The findings come as more than 40 percent of Americans report having trouble paying off their medical bills, and about half of insured adults worry about affording their insurance premiums.

On average, ACA plans costed $477 per month in 2024, according to data from Health Markets. 

For the new analysis, KFF researchers analyzed 392million claims filed to ACA insurance companies in 2023, the latest data available.

Data was taken from public reports released by the federal Centers for Medicare and Medicaid Services (CMS). 

It did not include claims from private insurers, such as policies provided to people through their employers.  

Overall, ACA insurance plans denied 19 percent of total claims in 2023, an increase from 16 percent in 2022. 

This was the highest rate since 2015, during which 19 percent of claims were denied. This adds up to 73million claims.

In recent years, the lowest rate was 14 percent in 2018.  

Blue Cross Blue Shield of Alabama received just over 13million claims in 2023 and denied 4.5million, about 35 percent. 

UnitedHealth Group, which serves 20 states that use ACA insurance plans, received 14million claims and denied 4.6million, a rate of 33 percent.

And Health Care Service Corporation, serving four states that use ACA plans - Illinois, Montana, Oklahoma, and Texas - received just over 25million claims and shot down 7.3million, a rate of 29 percent.

Centene Corporation, the largest health insurer managed by Medicaid, saw the most claims at 83million. Of those, 11.4million were denied, adding up to 14 percent. 

Florida-based GuideWell Mutual Holding had the lowest denial rate of 6.7million out of 53million - 13 percent.  

In KFF's state-by-state analysis, Alabama had the highest rate of claim denials at 34 percent, which is likely due to the denial rate of Blue Cross Blue Shield of Alabama. 

Oklahoma followed closely behind with a rate of 29 percent, and Alaska had the third-most denials at 25 percent. 

Of the states included in the analysis, South Dakota had the fewest denials with a rate of six percent.  

The researchers said claims may also be denied multiple times. 

For example, if a patient's name is misspelled in the initial claim, making them unidentifiable, it may be denied again after being corrected due to a service not being covered. 

Insurance companies also varied widely in terms of reasons for denials.

For example, Cigna HealthCare of North Carolina shot down 30 percent of claims due to treatment not being 'medically necessary.'

And Blue Cross Blue Shield of Arizona denied 97 percent of claims due to a lack of prior authorization or referral. 

The researchers noted that a denied claim does not mean the insurance company will not ultimately pay the expense. Instead, a new claim may be filed. 

Recent research from Cornell University suggests 100million Americans - nearly one in three - are in some form of medical debt, largely due to lack of insurance and denied coverage. 

And an estimated eight percent of Americans - 26million - don't have any form of insurance.