More than 500 drivers were caught speeding in Wales each day in 2017, according to Freedom of Information data.
Figures from the Gwent, South Wales, Dyfed-Powys and North Wales forces showed there were 184,880 speeding offences, a rate of 506 per day.
It represents a rise of 8.1% from the previous year when 171,000 offences were captured in 2016.
Speeding charity Brake said the figures were "deeply concerning".
Gwent Police saw the greatest rise in offences - up 62% from 29,611 in 2016 to 47,992 last year.
Almost half of these came on the M4, between junction 24 (Coldra) and junction 28 (Tredegar Park), which recorded a total of 27,041 speeding vehicles over the course of the year.
A variable speed camera was installed in September 2016 and caught 13,000 drivers in its first six months of use.
In 2016, the busiest camera in Wales was the southbound camera on North Road in Cardiff, catching 8,418 drivers. This number fell to 6,496 in 2017.
South Wales saw the highest number of offences with 71,700, up from 66,086 in 2016 - an increase of 8.5%.
The number of offenders caught by North Wales Police fell from 62,501 to 51,768 in 2017 - down 17.2%.
The busiest fixed speed camera in this area was on the A483 dual carriageway at Rossett in Wrexham, which recorded just under 4,000 offences.
In the Dyfed-Powys area, the number increased marginally from 13,374 to 13,420, with the busiest camera, on the A449 at Cefn Barn, Powys, recording 900 speeding drivers.
The minimum fine for being caught speeding in the UK £100 and three penalty points.
If all fines were upheld in Wales, at least £18,488,000 will have been raised by speeding alone.
A spokesman for speeding charity Brake said: "The increase in speeding offences in Wales indicates a deeply concerning trend of unsafe driving behaviour.
"Increased police enforcement is welcome, however, we need more robust penalties in order to deter drivers from breaking the law and putting lives at risk on our roads."
Sgt Trystan Bevan from North Wales Police' roads policing unit said: "We are committed to making our roads a safer place for all who use them and we will continue to crack down on those irresponsible drivers who choose to ignore speed limits and drive irresponsibly, not only risking their own lives but the lives of others."