Q. Will Medicare paper claims that lack NPIs be rejected during the contingency period?

A. Medicare will treat paper claims the same as electronic claims for NPI reporting purposes. For some period after May 23,2007, Medicare fee for service (FFS) will allow continued use of legacy numbers; it will also accept transactions with only NPIs, and transactions with both NPI and legacy identifiers.

Effective May 23, 2008, the legacy number will NOT be permitted on any inbound or outbound electronic transaction or paper claim. Medicare FFS has been assessing health care provider submission of NPIs on claims submitted.

As soon as the number of claims submitted with an NPI for primary providers is sufficient to do so, Medicare will begin rejecting claims without an NPI for primary providers following appropriate notice.

Once a decision is made to begin requiring NPIs on claims, primary providers, i.e., billing, pay-to and rendering providers, must be identified by their NPIs or the claims will be rejected. All other providers are considered secondary providers and include referring, ordering, supervising, service facility, care plan oversight, purchased service, attending, operating and “other” providers.

Legacy numbers are acceptable for secondary providers until May 23, 2008.

Source: Centers for Medicare & Medicaid Services