The estimated cost of reminding teenagers to vote in the independence referendum has almost quadrupled.
In a document to the finance committee, the Scottish Government conceded the total cost of implementing the bill for next year’s poll could be as much as £76,000 more than first thought.
The Scottish Conservatives last night said a rise in administration costs raised concerns about the total estimate of £13.7 million being at risk of swelling.
Finance spokesman Gavin Brown said: “If the SNP can’t get even the most simple administrative aspects of this right, how can it be trusted to keep the main event in check?
“The grand total has already shifted significantly to well more than £13 million.
“People accept there’s going to be a cost associated with the bid to break up Britain, but there will come a point when it will be deemed a complete waste of money.
“We need the Scottish Government to get a tighter grip on this before we see any other areas slip.”
The paper showed two areas relating to the Scottish Independence Referendum (Franchise) which had risen.
It revealed the cost of adapting electoral management software had gone from £240,000 to £300,000, while the price of reminding young voters to register soared from just £6,000 to more than £22,000 after the Scottish Government included the high cost of postage.
A Scottish Government spokeswoman said the costs may not reach the top level stated in the document.