Wakefield Council is reminding residents that they can challenge their council tax band free of charge.
It comes after reports of firms targeting people in the district, saying they will do the work for them for a fee.
Although not illegal, the council is keen to make people aware that they save their money if they research it themselves.
Gillian Connolly, corporate director for business change at Wakefield Council said: “We are aware that private companies are approaching Wakefield district residents and charging them a fee to appeal against their council tax bands on their behalf.
“Whilst this is not illegal and residents may contract others to appeal for them we want to remind everyone that they can do it for themselves free of charge at the Valuation Office Agency.”
Details can be found at www.wakefield.gov.uk/council-tax/council-tax-appeals