Got an insurance quote? Don't expect it to be accurate.

About 80 percent of U.S. health insurance plans raise premiums above the original quoted price for a portion of their applicants, according to new analysis.

HealthPocket, a free website that compares and ranks all health plans, found that, on average, 18 percent of applicants see an increase. Among states, Pennsylvania fared the worst, with 32 percent of insurance applicants paying more than insurers first quoted, while other states saw no notable increase in premium costs.

 “Consumers cannot objectively compare health insurance premiums prior to application because insurers base their initial rates on the healthiest applicants, and for many these rates would not apply,” Kev Coleman, head of research and data at HealthPocket, said in a statement.

“When insurers wait until an application is reviewed to reveal the true monthly premium, it is impossible for consumers to know what health insurance plan is the least expensive for their circumstances,” Coleman said.

Researchers singled out Blue Cross Blue Shield as the worst offender, saying that eight out of the 10 companies who increased premiums on applicants most frequently were Blue Cross Blue Shield companies. Anthem Health Plans in Virginia, part of Anthem Blue Cross Blue Shield, raised premiums for more than two thirds of applicants. The nonprofit PacificSource Health Plans in Idaho was second highest within this ranking.

States including Maine, Massachusetts, New Jersey, New York, Oregon, Vermont, and Washington had no activity in terms of increasing premiums after application. These states use a form of community-based premium rating practice that requires insurers to disregard health status in determining premiums to charge.