The dossier, entitled "Mackay's Missing Millions", reveals that the cost of over-budget government projects and departmental waste since the SNP came to power now runs to £431.5m - more than the entire cost of the Scottish Parliament building.
The figure does not include other public sector cost over-runs in Scotland for which the Scottish Government has partial responsibility, such as rail and NHS projects.
When those are included, the total figure for public sector waste in Scotland since the SNP came to power rises to £947.7m.
The Scottish Conservatives are publishing the dossier today as they ramp up calls for the SNP Government to cut government waste – and hand the savings back to families and businesses in the form of much needed tax breaks.
It comes ahead of a historic budget this week in which – for the first time – the Scottish Government will set out income tax rates and bands for Scotland.
The SNP is refusing to back a tax cut for middle-earners proposed by the UK Government – despite the fact that even Jeremy Corbyn’s hard left Labour party supports it.
Instead, Finance Secretary Derek MacKay says he cannot afford to give Scots the same tax break that people elsewhere in the UK will enjoy.
It means Scotland will become the highest taxed part of the UK, with higher income tax rates and higher business rates than those which will apply south of the border.
Scottish Conservative shadow Finance Secretary Murdo Fraser says today:
"The SNP claims it can't afford to give Scots the same tax break as people will receive elsewhere in the UK because there isn't enough money."
"Our dossier published today shows that this is total nonsense. The money is there - it's just that it's being frittered away."
“Incredibly, SNP incompetence has cost Scotland more than the entire cost of the Scottish Parliament building – itself a by-word for massive waste.”
“Hundreds of millions of pounds has been frittered away on bungled IT projects and cost overruns.”
“So our message to the SNP this week is clear. Get back to the day job, cut the waste – and pass the savings back to families and firms who need a break.”
“The SNP has spent far too long obsessing about independence. In so doing, as our research shows, it has entirely forgotten to do the day job we pay Ministers to do."
“Enough of the excuses and the complaints. The SNP needs to sort out the mess they are making of government, and give a break to hardworking taxpayers and local firms right across Scotland."