CMS institutes 30-day billing window, effective Jan. 1. You're about to lose 26 months of billing privileges, effective Jan. 1. According to the 2009 Medicare Physician Fee Schedule, you'll be able to retroactively bill Medicare for services your physician rendered up to 30 days prior to the date he received his Medicare credentialing status. Medicare will consider the physician's effective credentialing date as the "date of filing," according to the Fee Schedule -- meaning "the date that the Medicare FFS [fee-for-service] contractor received a signed provider enrollment application that the Medicare FFS contractor is able to process to approval" (emphasis added). So make sure the application is complete, and submit any additional information the contractor requires for enrollment. Approval Is a 'Guessing Game' That's a huge difference from the current rules, which give you a full 27-month window during which you can retroactively bill. Despite several comments from medical practitioners requesting more than the allotted 30 days, CMS stood firm in its decision. For example: Outcome: "You can no longer just bill Medicare while waiting for your credentialing approval, unless the services were performed 30 days prior to the Medicare approval," says PECOS May Cut Enrollment Time Fast forward: You may be able to speed up your credentialing by using the PECOS system, says To learn more, visit www.cms.hhs.gov/MedicareProviderSupEnroll/02_Internet-basedPECOS.asp.