A report into governance earlier this year raised a number of concerns about the authority, including that it was in more than £1bn in debt.
The Council has since developed an Improvement and Recovery Plan which it is hoping to give final approval to at a meeting on Monday.
Bosses say it will cut Council debt by around £360 million, reducing it to about £700 million.
This lowers the average debt per resident from roughly £10,000 to £7,000.
The council says, over time, the goal is to reduce total debt to close to £100 million, similar to other district councils.
Earlier this year it said there would need to be £8.6m in savings by 2028/29.
Surrey is set to devolve in April 2027 when the county will be split into two East and West unitary authorities.
District and Borough councils will cease to exist in the county after that.
Council Leader Cllr Joanne Sexton said: “This administration is taking decisive action to fix the mistakes of the past Conservative administrations to make sure Spelthorne’s finances are sustainable, transparent, and compliant with national standards. These are tough but necessary steps to protect local services and secure the borough’s long-term future.
“As discussions continue around the future of local government in Surrey, we are determined to put Spelthorne in the strongest possible financial position.”
