Health insurance premiums for federal employees and retirees will rise an average of 6.6 percent next year, the lowest increase in nine years, the Bush administration said yesterday.

Still, an official with one federal employee union branded the increase "outrageous," noting that average employee contributions to their health premiums will rise faster than the portion paid by the government.

Linda M. Springer, director of the Office of Personnel Management, which oversees the Federal Employees Health Benefits Program, said the government has consistently provided workers more health care options while doing its best to hold down costs.

"[W]e are maintaining a high-quality health-care program that provides excellent benefits at a reasonable cost," Springer said in a statement.

Next year's increase will be the government's smallest since 1997, when average premiums rose 2.4 percent. Independent studies predict a 10 percent increase in health insurance premiums for private sector employees next year, OPM officials said. Federal employees will have 279 health care plans to choose from, up from 249 this year.

An employee with the standard family coverage under Blue Cross and Blue Shield -- the most popular plan, covering more than half of all participants -- will pay $17.53 more in premiums every two weeks, bringing the biweekly cost to $135.59. Standard coverage for an individual will rise by $7.36, to $58.07 biweekly.

Across all plans, a federal worker with family coverage will pay an average of $12.79 more in premiums every two weeks, for a total biweekly cost of $130.17. At the same time, the government will contribute $16.83 more toward that worker's health coverage, for a total biweekly cost of $306.82. The worker's portion of the premium will rise 10.9 percent, compared with a 5.8 percent boost in the government's portion -- the disparity that rankles the union.

"Federal workers are once again being short-changed," said Enid Doggett, a spokeswoman for the American Federation of Government Employees.

Similarly, for an individual, the average will rise $5.30 every two weeks, for a total biweekly payment of $57.66. The government's contribution for that individual's coverage will rise $7.71 every two weeks, for a total biweekly payment of $134.98. That is a 10.1 percent increase in what the individual pays, and a 6.1 percent increase in what the government pays.

The program provides health insurance coverage to about 8 million government workers, retirees and their family members worldwide, including many in the District, Maryland and Virginia.

Staff writers Stephen Barr and Eric Yoder contributed to this report.