Almost half of people are unaware that England's smoking ban will come into force on 1 July, according to a poll.
But the survey of 1,700 people, carried out for the Department of Health, found over 90% did know a ban was coming in.
With 50 days to go before the law changes, the government is launching an advertising campaign to spell out what it will mean.
The ban will bring England in line with the rest of the UK and ban smoking in all enclosed public places.
The survey also found more than two thirds of people said the legislation would not affect how often they went to the pub, while 15% said they would go more often and only 7% less often.
Ten per cent of those surveyed were not pub-goers.
A third said a smoke-filled atmosphere had been the main turn-off for going to a pub.
The poll also suggested 87% of non-smokers supported the legislation, while just 44% of smokers did so.
A separate survey of more than 1,100 businesses suggest 41% do not realise smoking rooms will need to be closed, while 53% are unaware that work vehicles will also be covered by the legislation.
The TV ad, which will run from Monday, will show a man walking through a variety of locations, including a cafe, pub, garage and office, to demonstrate that they will all be required to be smoke free.
Launching the ad campaign, Public Health Minister Caroline Flint said the aim is to ensure that everyone is aware of the new law, how it will affect them and what they need to do to prepare.
She told BBC News: "There's an awful lot of people, both smokers and non-smokers, who find working and socialising in an atmosphere that involves smoke not very pleasant but also not very good for their health.
"I think of the campaign as very much an upbeat, positive campaign. Also, it's about reminding people of all the different places where the law will apply because it's not just pubs and clubs, it is about workplaces.
"It is about if you're a mechanic working in a garage, it is if you're a taxi driver or working in a cafe or working in an office. So the adverts will reflect the range of places in which the legislation will apply."
She said she was confident that with support from the Department of Health and local councils, everyone should be ready by the 1 July deadline.