Derbyshire-based Collins Earthworks saw pre-tax profits nosedive to £4.7m from £16.8m previously as costs soared in the year to November 2022.
The firm blamed the removal of the red diesel rebate in the face of rapidly rising fuel costs.
Revenue at the business edged up 5% to £113m in the year while staff levels also jumped by nearly a third to 400.
Director Dave Collins said: “The profitability for the year has been impaired due to changes in government legislation on the use of red to white diesel, which has resulted in an increase in the costs during the year.”
He added: “As experienced by companies within the sector, there have been increased costs in stone, aggregate surcharges, and other products which are utilised on site, and the company is currently reviewing potential sources in order to reduce these costs.”
Collins said that the business continued to invest in onsite hybrid machines electric fleet vehicles and the potential use of all-electric 8-wheeler vehicles.
“The company remains confident that the turnover for 2023 will be in line with that of 2022, and that direct costs should be reduced in line with practices invoked by the board which should results in higher net profits for the next financial year.” said Collins.
Cash at year-end was down from around £6m previously to £4m.