Air travelers in the U.S. without a REAL ID will be charged a $45 fee beginning in February, the Transportation Security Administration announced Monday.

The updated ID has been required since May , but passengers without it have so far been allowed to clear security with additional screening and a warning. The Department of Homeland Security says 94% of passengers are already compliant and that the new fee is intended to encourage travelers to obtain the ID.

REAL ID is a federally compliant state-issued license or identification card that meets enhanced requirements mandated in the aftermath of the Sept. 11, 2001, terrorist attacks .

Obtaining the ID — indicated by a white star in a yellow circle in most states — means taking more documents to the motor vehicle agency than most s

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