The government has spent £13.25m on advertising for Pension Wise since 2014, with an additional £4.5m planned this tax year.
The figures were revealed in a letter from pensions and financial inclusion minister Guy Opperman to the Work and Pensions Committee (WPC) for its inquiry into the pension freedoms.
The minister said use of the guidance service had "increased significantly from a standing start in April 2015", largely as a result of the advertising. In particular, he noted Pension Wise saw "record levels of demand" - in terms of appointment books and website visits - following its January 2017 television campaign.
Further, TV, radio or other press advertising is the second largest referrer to the service, after providers, driving 29% of visits, he said.
"Advertising is a great way of reaching those people who are less engaged with their pension provider and pensions in general, many of whom would benefit from Pension Wise guidance," Opperman wrote.
"Pension Wise is learning from each round of advertising to improve how they target and coordinate campaigns to get maximum awareness and engagement amongst the eligible audience."
Meanwhile, separate advertising for its auto-enrolment (AE) campaign has cost £17.4m since April 2015, the same letter revealed. Another £7.3m is budgeted for this financial year.
Earlier this week, Opperman told the WPC there was no need to make Pension Wise guidance mandatory where a saver wants to transfer their defined pot, and also rejected suggestions take-up of the serve was "abysmal".
Pension Wise will soon be merged with The Pensions Advisory Service and Money Advice Service into a single financial guidance body in a bid to reduce consumer confusion over where to direct their queries.
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