A poll for Budget Van Insurance shows that 21 per cent of respondents did not intend to adhere to the smoking ban in work vans or vehicles.
The ban came into effect at the start of the month.
The findings also show over one in ten people remain unaware of how the legislation will affect them when smoking in work vehicles.
Despite more than a fifth of drivers claiming that they will ignore the ban, 61 per cent of respondents believe that smoking should be banned in all vehicles.
As a rule of thumb vans used by two or more employees in England will come under the smoking ban.
On the spot fines start at £30, with fines awarded by the court up to £2,500.
Vehicles with a roof that can be removed or stowed away are exempt.