Charges to attend the Godiva Festival, previously a free event, could rise under new council proposals.
The increase has been put forward as part of Coventry City Council's draft budget, which also include a 4% council tax rise.
The cabinet member for finance at the Labour-run authority said he did not think it would reduce visitor numbers.
But the city's opposition party leader said he felt "sadness" at the loss of the city's free festival.
A £2 administration fee for tickets was introduced for the first time earlier this year when Levellers, Feeder and Busted were among the musical acts performing.
This could increase to £4.70 in 2020.
The council said it is because it subsidised the festival by £380,000 and hopes the rise will help it reduce the contribution to £200,000.
John Mutton, cabinet member for finance, said: "If it does diminish attendance, and I am not convinced it will, we will have to revisit it."
But Gary Ridley, opposition Conservative leader, said: "Godiva is something that really brought people to Coventry and was the UK's largest free festival.
"We were very clear when the charges were introduced it would probably be the door opening for further charges in future and I suspect that will be the case even after this."
The council tax proposals would mean an increase of about £73 a year on a Band D property.
Other suggestions in the report include introducing parking charges at War Memorial Park, which could generate £300,00 per year for the authority; switching off street lights to save £250,000 and spending £850,000 less each year on roads maintenance.
A pre-budget report will be discussed at a cabinet meeting on 19 November and, if supported, will go out for public consultation.
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