The House of Representatives has passed a bill outlawing all caller ID spoofing "with the intent to defraud or deceive".
So no more prank calls - but more importantly, no more calls from criminals aiming to trick people into giving away banking information.
The sponsors of the bill, Eliot Engel and Joe Barton, cited an identity theft operation in New York City which netted its operators more than $15 million - and another where a woman used the caller ID of a pharmacist to trick a love rival into taking an abortion drug.
The inclusion of the words "with the intent to defraud or deceive" is intended to permit legitimate uses of the technology. Blocking Caller ID and calling anonymously is still allowed.
CTIA - The Wireless Association has welcomed the ban. "CTIA and the wireless industry support making caller identification spoofing illegal as the applications of such an activity are usually for malicious purposes," it says.
But this isn't strictly true.
Many large companies, for example, use ID spoofing to make sure that people returning calls are directed to a central number, rather than the direct line of the person that actually called them.
Where this is happening through a third party contractor, it could technically fall foul of the law - depending on how you interpret the word 'deceive'.
Voice over IP (VoIP) calls such as Skype are specifically covered by the bill, but could also create a grey area as they frequently involve spoofing. Google Voice displays the Google Voice number even when users are actually calling on their landline or cellphone.
The Federal Communications Commission now has the unenviable task of working out exactly how to enforce the new law. Those who break it could face a fine of up to $10,000 and a year behind bars.
The police and Federal agencies are exempt.