The 34-year-old reality star was riding on a Piaggio Vespa along High Holborn when he was pulled over by a police officer in February this year.
Laing, the founder of confectionary company Candy Kittens, admitted breaking the law by holding his phone in both hands as he drove.
He was prosecuted through the Single Justice Procedure, in a case dealt with behind-closed-doors. Laing was handed six penalty points and ordered to pay a £192 fine, £110 costs, and a £76 court fee.
PC Alexandra Day told the court she spotted Laing breaking the law at 3.02pm on Wednesday, February 15.
“I noticed that the rider of this vehicle was using a hand-held mobile device whilst driving”, she said, in a statement.
“The device was being held in both their hands to the front, in front of themselves.
“I stopped the vehicle and spoke with the rider. I confirmed they weren’t making emergency contact to the 999 service. I pointed out the offence where they admitted to using their phone.”
Laing was said to have made no official comment at the roadside.
The reality star and former Strictly Come Dancing contestant, a mainstay of Made in Chelsea since 2011, was initially sent a fixed penalty fine to the Notting Hill home he shares with wife and fellow TV star Sophie Habboo.
The Metropolitan Police said a criminal prosecution was launched when Laing failed to provide his driving licence details in response to the letter.
Laing pleaded guilty in the court case and offered no mitigation before he was sentenced, a court official said.
The star is regularly photographed riding around London on a scooter, and spoke in January at his difficulties in passing his car driving theory test.
He revealed live on radio that he had passed the test at the tenth attempt.