WASHINGTON — Most of the people choosing health plans under the Affordable Care Act — about 80 percent — are paying their initial premiums as required for coverage to take effect, several large insurers said Tuesday on the eve of a House hearing about the law.
But the health insurance industry said the total of eight million people who signed up included "many duplicate enrollments" for consumers who tried to enroll more than once because of problems on the website.
"Insurers have many duplicate enrollments in their system for which they never received any payment," said Mark Pratt, a senior vice president of America's Health Insurance Plans, an industry trade group.
"It may be a matter of months," Mr. Pratt added, "before insurers know how many people activated their coverage by paying their share of premiums."
President Obama said last month that eight million people had signed up for health insurance under the Affordable Care Act, surpassing the administration's original goal of seven million in the federal and state insurance exchanges.
In testimony prepared for a hearing of a panel of the House Energy and Commerce Committee on Wednesday, Mr. Pratt said, "Health insurers have been doing everything possible to encourage exchange enrollees to pay their premiums."
Paul Wingle, the executive director of exchange operations and strategy at Aetna, said: "As of the third week of April, Aetna had over 600,000 members who had enrolled and roughly 500,000 members who had paid. For those who had reached their payment due date, the payment rate, though dynamic, has been in the low- to mid-80 percent range."
Aetna said it was selling insurance to individuals and families in the exchanges of 17 states.
The Obama administration extended deadlines for people to sign up and pay for insurance, making it difficult to establish an accurate count of enrollment, insurers said. The federal government is still working on a financial management system to reconcile enrollment records of insurers and the exchanges.
J. Darren Rodgers, the chief marketing officer of the Health Care Service Corporation, which offers Blue Cross and Blue Shield plans in Illinois, Montana, New Mexico, Oklahoma and Texas, said his company had received 600,000 applications through the exchanges in Texas and the four states it serves. On average, according to data provided by Mr. Rodgers, about 15 percent of customers missed their initial payment deadlines from January through April.
About two-thirds of Aetna subscribers with exchange policies scheduled to take effect on May 1 have paid their premiums, Mr. Rodgers said, but some of the others have more time to pay.
Dennis Matheis, the executive in charge of exchange strategy for WellPoint, said the company was satisfied with returns on its business in the 14 states where it was selling health plans on the exchanges.
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"We are seeing strong membership growth and large percentages of our newly enrolled customers are successfully paying their premiums by the due date," Mr. Matheis said.
For people who signed up from Oct. 1 to April 15, Mr. Matheis said, about 70 percent have paid their premiums. For people who have passed the payment deadline, he said, the proportion is higher, "ranging up to 90 percent, depending on the state."
Republicans on the committee said last week that only about two-thirds of people signing up for private health insurance in the federal exchange had paid their premiums as of April 15. Administration officials and congressional Democrats called that statistic grossly misleading. Given the surge in enrollment near the end of March, they said, it is understandable that some policyholders would not have paid by April 15.
Frank E. Coyne a vice president of the Blue Cross and Blue Shield Association, said 283,800 people had signed up for coverage offered by "multistate plans" sold by Blue Cross and Blue Shield under contract with the federal government.
Congress authorized the multistate insurance program to increase options for consumers shopping in the online insurance markets. The plans are available in the marketplaces, or exchanges, of 30 states.
—By The New York Times' Robert Pear.