Unveiled in October, the TV, print and bus adverts aim to encourage smaller companies to get ready for providing workplace pensions.
When it was launched, the DWP was unwilling to reveal the cost of the campaign, but said it had budgeted £8.54m for advertising campaigns during the 2015/16 financial year.
However, now according to the governmental department, around £9.6m has been set aside to spend in 2016/17, £9m has been budgeted for 2017/18 and around £9.9m will be allocated to 2018/19.
During 2019/20 - the last year of the campaign - the budget is expected to be chopped to £6.6m.
This means that overall the campaign could cost a total of £43.6m.
A DWP spokeswoman said: “Automatic enrolment affects the vast majority of employers and workers in this country, so it is crucial that we do our best to help everyone understand what they need to do.
“Encouraging people to save for later life has the potential to improve millions of people’s lives and is a key priority for the Government, so it is right to promote this policy.”
The spokeswoman said there has been an increase of around 350 per cent in the number of employers visiting the Pensions Regulator’s website in the four weeks since the campaign launch.
This has amounted to a weekly average of 28,263 unique visits to the employers page. This figure rose to 126,805 in the month after the campaign launched.
Almost half of these employers, she added, went on to use the Pension Regulator’s duties checker, which shows employers what they need to do to comply.
Paul Lindfield, director of wealth management at Sedulo Wealth Management, said: “Awareness does need to be raised.
“It would probably be more powerful if people understood that state pensions are funded on a pure week-on-week basis by national insurance contributions, and that state pensions are not sustainable with an ageing population.
“If you don’t fund your own pension then you face the final third of your life in poverty, which is not good for DWP or the politicans.”
Mr Lindfield said the amount budgeted sounds a lot of money, but if the campaign raises awareness, increases employer willingness to fund more than the phased minimums, and reduces optouts, then it is a positive thing.
He said so far the campaign has raised awareness of work place pensions, but not the reasons why it has been brought into effect and why people need to act.