CMS has extended the Medicare participation enrollment period. Physicians who wish to change their Medicare participation status for 2007 have until February 14 to do so. Changes in participation status will be effective January 1, retroactively if necessary, regardless of when the participation decision is made.

A participating physician must accept Medicare allowed charges as payment in full for all their Medicare patients. A nonparticipating provider can choose to accept or not accept assignment on Medicare claims on a claim-by-claim basis. Once made, Medicare participation decisions are binding for the entire year.

Physicians may also choose to opt out of the Medicare program entirely. Physicians who opt out of Medicare are bound only by their private contracts with their patients (although Medicare specifies that these contracts contain certain terms). You may choose to opt out at any point in the year, but once you opt out, you cannot opt back in for two years.