Delaying the requirement for people to buy insurance under the Affordable Care Act could have negative consequences for the insurance market, including the prospect that insurers could collect less in premiums than they ultimately have to pay out in claims, resulting in higher rates. That's the stark warning issued by the American Academy of Actuaries in a letter to Congress this week.
"We were aware of some legislative proposals," said David Shea, vice president of the academy's Health Practice Council, "and we just wanted to make some folks aware that there are some potential consequences to a delay."
A growing number of lawmakers from both parties have called for delaying the Obamacare individual mandate penalties for those who don't buy insurance, in the wake of the rocky rollout of HealthCare.gov. The technical troubles that have plagued the online insurance marketplace have made it difficult for Americans to sign up for insurance coverage.
Insurance analysts say that without the requirement to buy insurance, it's more likely that mostly sicker people will enroll for coverage. It's what's known in the insurance industry as adverse selection. Insurers based their 2014 rates on the assumption of an individual mandate and a limited period for open enrollment. Without enough healthy people to offset the costs of patients who use a lot of medical services, that could mean premiums won't be enough to cover their claims.
Extending the deadline for enrolling in coverage beyond next March could prove just as negative as delaying the individual mandate itself, said Shea.
"The further out you extend it, the greater the potential consequences," he said.
While the government has established certain risk protections to help offset the possibility of adverse selection for insurers for the first three years of Obamacare, without younger, healthier people in the insurance pool, the actuaries say federal officials could be on the hook for larger-than-expected payments under the risk program. And the ripple effects would likely continue beyond next year.
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"The premiums in 2014 won't change," Shea said, "but it could have an impact on increasing premiums in 2015."
Insurers will begin to look at pricing rates for 2015 next spring and summer. They've already made certain assumptions on rates this year, based on the individual mandate prompting more people to enroll. If the enrollment numbers prove wrong, they won't likely make the same assumptions next year.
Shea said if the technical issues on HeatlhCare.gov persist for a long period of time, extending the enrollment period may be necessary. But legislators should know that there will be consequences.
—By CNBC's Bertha Coombs. Follow her on Twitter: