You can share your home by using a service like Airbnb.

So, why not share the cost of your medical treatments?

That’s one of the arguments behind so-called health cost savings programs.

These groups, most of which are religious based, have seen double digit increases in memberships the past few years, thanks in great part to an exemption they received to requirements in the Affordable Care Act (ACA).

Since the Obamacare law went into effect in 2010, it’s estimated the number of people in the United States enrolled in health cost sharing plans has more than doubled from 200,000 to 530,000.

Officials at Samaritan Ministries told Healthline their membership has jumped from 22,000 households in 2013 to its current 62,000 level.

Supporters of these plans say they are more affordable, provide more choice, and are more personal as opposed to corporate.

Critics, however, say the ministries are unregulated, don’t guarantee claims will be paid, and could hurt the overall healthcare industry by pulling a segment of the country out of the insurance market.

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How It Works

Health cost sharing groups have been around for more than 20 years.

They originally formed because of rising health costs in the 1990s.

It’s estimated there are at least 50 health sharing ministries in the United States. A report by the National Association of Insurance Commissioners (NAIC) estimated those groups oversee about $60 million in healthcare payments a year.

Many of these ministries are small, but there are three large organizations.

They are Samaritan Ministries, Christian Care Ministry’s Medi-Share, and Christian Healthcare Ministries.

The rules vary from group to group, but there are some basic tenets most follow.

Most require members to go agree to a code of conduct before they enroll. This pact requires members to follow Christian-supported behavior. They can mean no smoking, limited drinking, and no premarital sex.

Households pay anywhere from $75 to $500 a month depending on their size and other factors. An average monthly stipend seems to be around $400.

Sometimes members pay into a ministry pool. More often, they are directed to send their money to a specific family to help with medical costs.

An administrative arm of the ministry decides whose bills are reimbursed and who donates to which family.

Most ministries will not help pay for medical services they say go against their Christian faith. At the top of that list is abortion.

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Lower Costs, More Caring

There are a number of reasons supporters like this setup.

One is the cost. Ministry officials estimate their members pay up to 30 percent less than people with traditional insurance coverage because there is no corporate overhead.

However, Anthony Hopp, director of membership development at Samaritan Ministries, says there’s a lot more to it.

Hopp told Healthline that Samaritan members like the personal nature of their group. They know whom their money is going to and many times send along cards and prayers.

His May payment of $405, for example, went to another member who had a hernia operation.

Hopp said the sharing of the “emotional and spiritual burden” means more to members than the sharing of the financial burden.

“It’s person to person,” he said. “People taking care of each other.”

He added that members also feel secure knowing their money isn’t going to a medical procedure to which they are opposed.

“Most join out of principle,” Hopp said. “It’s an operation consistent with their religious values.”

Twila Brase, the president of the Citizens’ Council for Health Freedom, told Healthline the ministry health sharing programs also give members freedom of choice.

They can go to the doctor and hospital they choose and still get reimbursed.

She added the members are also more selective when making medical decisions because they personally know who is helping pay for it.

She said costs are sometimes lower, too, because members are paying cash and their medical providers are not dealing with an insurance company.

“It brings cost-consciousness to every healthcare decision because there is no big pocket in the background,” said Brase, whose group doesn’t oversee any health cost sharing programs but supports the concept and the organizations.

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Concerns, Criticisms

The health sharing groups might not be appealing to a lot of folks if it wasn’t for the exemption to Obamacare that Congress granted the ministries.

Among other things, the exemption relieves members of ministries that were formed before 2000 of the ACA’s individual mandate requirement.

Since the ministries are not insurance companies, their members would be required to pay a fine every year for not having signed up for health insurance if the exemption were not in place.

Critics say the exemption is unfair to people who are not close followers of a Christian faith.

They also say the ministries are siphoning off healthy individuals from the country’s insurance pool, weakening the industry as a whole.

“I think health sharing ministries seem to be terrific institutions for most of the people in them, but I do have concerns about their effects externally,” Rachel Sachs, an academic fellow at the Petrie-Flom Center for Health Law Policy, Biotechnology and Bioethics at Harvard Law School told U.S. News & World Report in a February article.

Hopp and Brase, however, rejected that notion.

Hopp said the membership of the ministries nationwide is only 2 percent of the total insurance market, a number too small to affect the industry.

He added many people with chronic ailments and pre-existing conditions join the ministries, taking those more expensive patients out of the insurance pool.

Another criticism leveled at the ministries is the limited services.

Besides abortion, some groups do not cover preventive care, dentistry, vision, and mental health services.

They also point out the ministry code of conduct might be OK for adults in the programs, but they might not cover actions taken by, say, teenage children.

Hopp and Brase said the limits are well-known to those who sign up and are part of the price of being a member.

“We recognize this option is not for everybody,” said Hopp.

Critics also say that since the ministries are not regulated, there is no guarantee members will be compensated, and if there is a disagreement they are not allowed to sue their group.

Hopp explained there is an appeal process at Samaritan Ministries. Members can ask a panel of 13 randomly chosen individuals to review a claim. He said there have only been four such incidents in the past two decades with his group.

“There aren’t many insurance companies that offer this kind of consumer protection,” he said.

Brase agrees.

“The industry itself doesn’t make guarantees,” she said.

The ministries are required to perform annual audits.

This was instituted after at least four lawsuits were filed against different ministries between 2000 and 2008 involving disputed claims.

The legal actions were against Christian Healthcare Ministries and Medi-Share.

Despite the criticisms, Hopp and Brase said the ministries provide an alternative for people who want a more affordable, faith-based healthcare system.

“It’s voluntary,” said Brase. “Nobody has to join.”