The estimated average Part D monthly premium will increase by as much as $3 in 2008, according to an announcement from the Centers for Medicare & Medicaid Services.

While actual individual plan premiums are yet to be announced, CMS said it expects the average monthly premium for the Medicare prescription drug plan to be $25 in 2008. The agency attributes the increase over 2007 premiums to a “normalization” of the risk-adjustment model, which allowed for higher reimbursements to plans for sicker enrollees.

Nevertheless, some beneficiaries may have plan options next year with premiums below what they are paying this year, CMS stated.