Susan Tucker, 54, did not want to be locked into networks that would prevent her from seeing the doctors she wanted. Instead, she opted for the Christian Heathcare Ministry, which she says will allow her more flexibility and choices. (Edward Linsmier for The Washington Post)

Susan Tucker is one of millions of Americans who dislike the health law and want nothing to do with it. But the 54-year-old Venice, Fla., homemaker took her opposition a step further: She opted out.

Tucker dropped the private health plan she had carried for more than a decade and joined Christian Healthcare Ministries, a faith-based nonprofit in which members pool their money to pay for one another’s medical needs — and promise to adhere to biblical values, such as attending church and abstaining from sex outside marriage.

“When all this came up with the ACA, I just realized I don’t want to be a part of any of this,” said Tucker, who views the Affordable Care Act as the government meddling in her personal health care. The Christian Healthcare program is not as comprehensive as insurance — she has to pay for her preventive care, for example — but the monthly payment of $150 can’t be beat, she said.

Tucker is part of a small but growing group of Americans whose opposition to the Affordable Care Act is spurring them to seek out alternatives, choosing once-fringe methods to pay for their medical care in an effort to skirt the many requirements the law imposes on the private health insurance market.

The result is a burgeoning business among brokers, clinics and insurers that are advertising themselves as a way to avoid the sweeping federal program. The options range from Christian co-ops such as Tucker’s to membership-based primary-care clinics to insurance policies that cover specific diseases, such as cancer.

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In some cases, such as Tucker’s, the options are permitted by the health law; the people who sign up don’t have to pay the penalty for not carrying adequate coverage. In other cases, the options are not sanctioned by the law, leaving people on the hook to pay the fine. But some critics of the law say that even with the penalty, the alternatives are worth it.

Advocates and health-policy experts say there are risks in addition to the penalty. The programs typically do not carry the law’s consumer protections, such as a bar on insurers refusing to cover preexisting conditions. Consumers won’t be eligible for federal subsidies to help them pay their premiums. They could get stuck with unpaid medical bills.

While some of the plans might “make sense” for healthy consumers, “a lot of this stuff is truly just junk coverage,” said Sabrina Corlette, project director at Georgetown University’s Center on Health Insurance Reforms. She said consumers should be especially wary of specialty or partial plans being marketed as traditional coverage.

Critics of the health-care law counter that these options can be a good deal for consumers — even if they have to pay the penalty. Because many of the plans do not include mental health or maternity coverage, they can be cheaper than the policies offered by the new online marketplaces. And since the plans often do not create networks of doctors, patients are free to choose the physicians they want.

There is a “parallel free market that exists alongside the conventional market” for health insurance, said Sean Parnell, a public policy consultant who has become a guide for the opt-out crowd with his blog and book called “The Self-Pay Patient.” “What I tell people is, there are alternatives.”

The Affordable Care Act was intended in part to standardize individual policies to ensure that people were buying comprehensive coverage — and not plans that, for example, refused to cover unexpected pregnancies. The law established categories of medical care that must be covered, including contraception. But those requirements have sparked a backlash among people who oppose the idea of paying for others’ birth control and those who consider the requirements onerous and costly.

One alternative has already been swatted down by the Obama administration. “Fixed-benefit” plans give beneficiaries a predetermined amount for injuries and illnesses — for instance, $1,000 a day for a hospital stay or $30 for a doctor visit. But those amounts could leave patients on the hook for potentially thousands of dollars if the actual costs exceed those payments.

Some companies had promoted these plans, which are typically used as an extra layer of coverage on top of standard health insurance, as a substitute for traditional insurance. Last month, federal health officials banned the sale of most such plans as stand-alone policies beginning in January 2015.

Some other alternatives, however, are tolerated or even encouraged by the health-care law — to promote innovation or religious freedom, or because it was not expected that large numbers of people would enroll.

People who sign up for certain health-care ministries are exempt from the law’s penalty for people who lack insurance. Direct primary-care­ clinics, which provide around-the-clock access to doctors for a monthly fee, can apply to the federal government on a case-by-case basis to be considered acceptable coverage under the law.

There are short-term plans that can be purchased for part of a year and are often cheaper than the policies sold via the online marketplaces. But in these cases, the insurers can still reject those with preexisting conditions. The short-term plans often do not cover mental health or maternity care. And people who sign up may have to pay the penalty, just as if they were uninsured.

Parnell, the blogger, joined one of the Christian health-care sharing ministries, which have been around for years but are flourishing. They do not consider themselves insurance, nor do many state insurance departments. Conservative lawmakers have encouraged the ministries, with 28 states passing laws that explicitly exclude the ministries from state insurance regulations.

All of the ministries work slightly differently. One of the oldest, Samaritan Ministries, based in Peoria, Ill., has members send monthly checks not to a central office but directly to people in need. It not only requires people to sign a pledge to adhere to Christian values, but it also asks for an annual sign-off from a deacon or pastor attesting that the person is being truthful.

“Beyond that, we just leave it up to the spirit to convict that person if they decide to lie,” said Joel Noble, public policy manager for Samaritan as well as the Alliance of Health Care Sharing Ministries.

Noble has been a member of Samaritan for 13 years. “I’m expecting my fourth child in July,” he said. “I probably have 21 checks sitting on my desk at home waiting to be cashed.”

He said Samaritan is adding about 1,000 families a month — up from about 700 a month a year ago.

Christian Healthcare Ministries, which Tucker joined, has existed since the 1980s, but membership has surged — growing by 60 percent to more than 80,000 members — since the health-care law was passed. The most popular plan costs $150 a month per person and covers medical bills up to $125,000 for any single illness or incident. People with higher bills are covered if they belong to a special program in which members split the cost. This “brother’s keeper” program typically costs less than $100 a year, according to the group.

While Tucker is a member, her husband is not because he smokes, which the ministry forbids. He pays Blue Cross Blue Shield $840 a month for a plan he purchased independently of the marketplaces, which he did not use because of the couple’s opposition to the health law.

Experts warn that there is significant risk in joining these ministries. Dissatisfied consumers often cannot turn to state insurance departments to resolve disputes — and they may be limited in their efforts to pursue grievances through the courts. Members of the ministries also are expected to negotiate with hospitals to reduce their bills, something hospitals often do for uninsured patients.

Disputes have arisen in Montana, Illinois and elsewhere between ministries and their members over unpaid bills. But longtime members say the ministries work, even when it comes to serious illnesses such as cancer.

Norma Beech, 67, has been a member of Christian Healthcare Ministries since 1991. The retired secretary from Port St. Lucie, Fla., used the program for her husband and two children. She underwent chemotherapy and a costly bone marrow transplant when she was diagnosed with non-Hodgkins lymphoma.

She negotiated with her doctors and hospitals, who agreed to reduce the amount she owed from more than $1 million to closer to $350,000, she said. Christian Healthcare Ministries then sent her checks for the rest. “You have to be pretty honest and say, ‘That money goes right to paying my doctor’s bill,’ ” she said.

Unlike insurance companies bound by the health law, these ministries typically do not pay for contraception, abortion or treatment for most mental illnesses. An injury arising from what is considered non-Christian behavior, such as a drunken driving accident, may not be covered.

“These ministries operate on a very high degree of trust,” said Timothy S. Jost, a Washington and Lee University law professor and consumer advocate. “It’s really important that people really believe in this and are committed to this. If you have a bunch of people sign up who are doing this only to [avoid the health-care law], the whole thing can collapse.”

At least one ministry has taken a more liberal approach to the religious aspect. Liberty HealthShare, which is based in Ohio, accepts non-Christians as long as they adhere to certain values, including the belief that “it is our fundamental right of conscience to direct our own healthcare, in consultation with physicians, family or other valued advisors, free from government dictates, restraints and oversight.”

It is an option that appeals to Anthony Wilson, 56, a southeast Indiana engineer who never warmed to the health law and planned to stick with his old health plan — until Anthem said it would be raising the rate for him and his wife to more than $1,400 a month.

He said that the Liberty plan has shortcomings but noted that it is cheaper than the Anthem policy and aligns with his Catholic faith. And he is happy that he is not participating in the health-care law. “I would prefer to not be a part of that if I can,” he said.