Bolton appointed Coyle in January to replace Megson
Bolton's financial losses nearly tripled last season due largely to the cost of changing manager and strengthening their squad.
According to accounts for the year ending 30 June, Wanderers' losses rose from £13.2m to £35.4m.
This includes £4.2m for sacking Gary Megson and prizing his replacement Owen Coyle away from Burnley in January.
The club spent £15m on recruits with no senior players leaving as their wage bill rose 14% from £40.9m to £46.4m.
This included the signing of midfielders Chung-Yong Lee and Sean Davis and defenders Zat Knight, Paul Robinson and Sam Ricketts. They also brought in forwards Ivan Klasnic and Jack Wilshere on loan.
We have plans in place to progress the football club. We will be looking to an improved financial position year on year
Bolton chairman Phil Gartside
Overall, the club's net debt rose to £93m from £64m.
Chairman Phil Gartside admitted the club now have a surplus of players, but it remains financially sound and will not be forced to sell any of their prized assets.
"The cost of transition from one manager to another is always expensive, and we have got a player transition where we have a surplus on the playing staff of about six or seven players," added Gartside.
"We wanted to shed players in the summer to bring the wages down but we couldn't because the market has died.
"We are trying to control costs, we are trying to reduce our wage bill and that will continue.
"We are a trading club, we are not a selling club. There will be times when we have to trade players and that is our goal in the next few years."
Gartside also said that owner Eddie Davies, who took control in 2003, remains committed to the club.
"We are in a fortunate position in that a small percentage of our debt is owed to the bank," said Gartside.
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