Almost 70,000 drivers have been caught by the state's mobile phone detection cameras in six months.
Revenue NSW data shows 69,659 people were fined between March and August, netting the NSW government more than $31 million in fines revenue.
The cameras were introduced in December, but for three months offenders were sent warning letters.
From March 1, those caught were hit with a $349 fine ($464 in a school zone) and lost five demerit points.
More than 10,000 drivers were being caught each month up until last month, when the number of offenders halved between July (13,825) and August (6036).
There is believed to be about eight cameras in operation around the state, but the government plans to have 45 rolled out by 2022-23.
A transportable, trailer-mounted camera has been used on a number of Hunter roads, including Griffiths Road at Broadmeadow.
Transport for NSW deputy secretary of safety, environment and regulation,Tara McCarthy, said the cameras were moved regularly to ensure enforcement did "not become predictable".
"Cameras have been deployed statewide and transportable cameras are regularly moved to different sites across the network," she said.
"The number of days at each site will differ so that enforcement does not become predictable.
"This reinforces to all drivers they need to get their hand off their phone and know the rules no matter where they are."
While mobile phone detection cameras have caught a staggering number of offending drivers in the first six months, the number of police-issued fines for using a mobile phone has fallen over recent years.
NSW Police handed out 19,411 fines in 2019-20, down from 31,499 the year prior and 41,848 in 2017-18.
Revenue from police fines totalled $6.7 million in 2019-20, less than half what was collected two years prior - $13.8 million in 2017-18.
Illegally using a mobile phone while driving is associated with at least a four-fold increase in the risk of having a crash in which someone is killed or seriously injured, Ms McCarthy said.
Texting while driving increases the crash risk even further.