The Scottish government spent one fifth of a £450,000 public information budget on billboards to publicise its White Paper on independence.
The posters were part of a publicity campaign announced last November.
A freedom of information request revealed the adverts were pasted on 189 billboards across Scotland for a two-week period at a cost of £84,160.
The Scottish government said the campaign was targeted at all adults and "large format billboards" were used.
The BBC research found that the majority of campaign posters were located in Glasgow and Edinburgh.
- You can see where these billboard posters were placed, and how much each one cost, using the interactive map developed by BBC Scotland.
The freedom of information request also included an extract from the creative brief written by marketing firm The Leith Agency in mid-August 2013.
The document stated, "This is not a political campaign. This is a public information campaign to make people aware that this document is available."
However, John Pentland, Labour MSP for Motherwell and Wishaw, believed it was politically motivated.
He said: "Considering the White Paper is a party manifesto, I started to ask parliamentary questions because I was concerned that the resources of the government had been used as an extension of the Yes campaign.
"My constituency got the heavy treatment with the use of 11 posters, so I wonder why we deserved such largesse with well over £3,000 spent on decorating our billboards with Scottish government propaganda."
The costs for placing one poster ranged from £300 to £1,865 depending on the location of the billboard.
Due to commercially sensitive information, the released figures did not include any additional costs associated with the two marketing and media-buying agencies used for the campaign.
A Scottish government spokeswoman said: "The volumes selected in each area are based on industry weights that take into account the population and number of sites in each city to ensure that the campaign is as efficient as possible.
"We also had to take into consideration the availability of panels at the time of booking."
In addition to the billboards, the spokeswoman said a series of press advertisements, home-delivered leaflets, social media activity, and localised events ensured no community was neglected.
SNP MSP David Torrance said the five billboards placed in his constituency of Kirkcaldy had been well-received.
He told the BBC: "I believe [the billboards] have helped people become even more engaged in the debate on Scotland's future - which can only be a positive thing.
"The more people find out about the gains of independence the more likely they are to vote Yes - as polling evidence shows with the Yes vote continuing to rise."
However, Alex Fergusson, the Conservative MSP for Galloway and West Dumfries, and Liberal Democrat MSP for Shetland, Tavish Scott, said the positioning of the posters was "politically strategic".
Neither politician had had the billboard publicity campaign in their constituencies.
Mr Scott added he was not surprised the focus had been on constituencies like Mr Pentland's.
He said: "It's the Labour vote they need to switch to win the referendum and these billboards, with their subliminal message, is one way of doing that."
But John Curtice, a politics professor at Strathclyde University, said it was unlikely the posters have been strategically placed in key vote areas.
He explained: "In so far as the billboards will consequently be in areas with substantial passing traffic, including people who live some distance away, it is very difficult to see how one can argue they are closely targeted at any particular group.
"The survey evidence consistently suggests that women are more likely to say they are undecided or say they might change their minds, but women are not geographically segregated."
Professor Curtice added the distribution of the posters could also simply reflect the distribution of billboards in Scotland, which could be limited in some areas due to local planning laws.