The council has pocketed an extra £50,000 from on-road parking bays in the last year – despite a drop in drivers using them.
Official statistics show a 12 per cent rise in profits during 2011/12, compared to the previous year.
And all the surplus cash must be pumped back into the city’s transport network, including filling potholes and giving bus passes to the elderly.
The local authority said despite a fall in income its profits from on-road parking had jumped thanks to “more efficient ways of operating”.
Plymouth City Council made £451,000 last year, compared with £402,000 in 2010/11. During that time there have been budget cuts landed on the council and redundancies among some of its staff.
As The Herald has reported previously, the council’s overall profits from pay-and-display machines in 2011/12 stood at £2.9million.
The latest parking profits figures, compiled from official council data, were released by the Institute of Advanced Motorists (IAM).
For Plymouth, they only cover on-street parking bays – and not designated car parks.
At £38million, Westminster City Council in London posted the fattest profits in the country.
The IAM says it is concerned that councils in England made over £411million in parking charges last year – up nearly 15 per cent – while at the same time the amount spent on road safety, education and safe routes to schools plummeted by £22million, or 18 per cent.
The organisation’s chief executive, Simon Best, said: “Councils are making record-breaking profits from parking, while cutting road safety spending.
“At the same time cuts to road maintenance will mean a backlog of repairs which will simply cost more to fix in the long term.”
Plymouth is not alone in having to cut spending on road maintenance – mainly thanks to budget cuts enforced by the Government.
A council spokeswoman confirmed parking income had fallen over the last financial year.
But she added: “In spite of this, we have managed to increase our overall surplus by introducing new, more customer friendly technology – for example pay-on-foot systems in car parks – and more efficient ways of operating.
“Like other councils we are facing significant budget cuts and a reduction in our highways maintenance budget.
“This means we have far less to spend on roads and transport initiatives.
“Surpluses from parking revenue help lessen the effect of these cuts as they must be spent on transport services such as filling potholes, bus passes for the elderly, park and ride schemes, street lights, parking services and road improvement projects – things that benefit all road users at some point.”