Newcastle council has raised the cost of parking at No.2 Sportsground by $2 a day to make sure "parking is more evenly distributed across the CBD".
The council started promoting the nearly vacant 200-space car park last year as Newcastle's rapid redevelopment gobbled up other parking in the inner-city.
The Newcastle Herald reported in February that the Smith Street parking lot had gone from virtually empty to virtually full in the space of a year as motorists took advantage of a $6-a-day price tag, or $5 using the council's parking app.
On July 1, the council raised the cost of all-day parking at No.2 to $8, or $7 on the app, which is equivalent to parking charges elsewhere in the city.
Asked about the price rise on Wednesday, a council spokesperson said: "The cost of all-day parking at No.2 Sportsground used to be discounted to encourage parking in Newcastle West which was until recently significantly underutilised.
"The car park's popularity has now grown to the point that as of the start of July we brought the price into line with other city centre car parks so that parking is more evenly distributed across the CBD."
A motorist who spoke to the Newcastle Herald said she had received a $114 fine on July 19 at No.2 Sportsground after putting $6 into a parking machine and displaying what she had assumed would be an all-day ticket in her car.
"I've been parking there for over 12 months, and I didn't know it had changed," she said.
"I just threw the coins into the machine and got a parking fine. I thought, 'When did that happen?'
"There's no signs up, just tiny little writing on the machine that says $8 a day.
"If they're going to change it overnight, couldn't they put it up on the sign when you drive in?"
The council said on Wednesday that it had collected $5.7 million in parking revenue in 2018-19, up from $4.69 million the year before.
The council announced recently it would continue to subsidise the Hunter Stadium park-and-ride service for another year after the NSW government stopped funding it after the state election.