Auditor General Caroline Gardner gave the updated figure - which she called a "conservative" estimate - to MSPs on Holyrood's audit committee during a scathing assessment of the Scottish Police Authority.
The committee has now called on the SPA, Chief Constable Phil Gormley and the Scottish Government to appear before it to explain the "financial mess".
Giving evidence earlier, Ms Gardner said there was a "weak financial leadership" in both Police Scotland and the SPA.
She said: “Since the establishment of (Police Scotland and the SPA) in April 2013, this has been an ongoing problem and one that has not yet been resolved.
"This would be unacceptable in any public body let alone ones the scale and importance of the SPA and Police Scotland.
"To illustrate the scale of the future financial challenge, I have updated my projections of the potential funding gap facing the SPA and Police Scotland.
"These suggest a cumulative deficit of almost Â£200m in real terms by the end of this parliamentary session. I consider this projection to be conservative."
SNP MSP Alex Neil, a member of the committee, said the SPA was an organisation in "crisis".
Speaking later, committee convener Jenny Marra said: “It was incredibly worrying to hear today that the Scottish Police Authority’s cumulative funding gap – initially projected to be Â£188 million – may, according to the Auditor General, rise to almost Â£200 million.
"The Audit Committee is calling for the Chair and Chief Executive of the Scottish Police Authority, the Chief Constable and the Scottish Government to come before us to get some clear answers on this financial mess and to find out why no progress is being made despite continual warnings.”
A spokeswoman for the SPA said: "Over the past year, we have carried out a major refresh and strengthening of the leadership team at the helm of policing, with more to come.
"We have put more finance staff into policing to address capacity and capability, and addressed the specific financial issues around fixed asset reporting. We look forward to providing Parliament with further assurance on these when we give evidence in due course.
"While we have acknowledged issues around policing's financial performance, the operational performance of the service remains strong.
"We are not complacent about that because we know that the demands on policing are changing, with an increasing emphasis on vulnerability, private space crimes, and online threats. Addressing that within the level of resources available is challenging."