Alin Badea, chief executive of Royal Cars, a taxi firm in Tunbridge Wells, said its drivers were having to pay an extra £300 a month for petrol.
“We are having to increase taxi fares, and we try to be as reasonable as possible,” he added.
“Customers understand the situation, but if this keeps going, we can’t sustain the businesses.”
Badea said the firm has seen a 20% drop in business.
Tudor Price, chief executive of Kent Chamber of Commerce, said: “If the government wanted to see a growth in our economy, an intervention is required.
“This could be temporary relief of business rates, reduction of fuel VAT or rolling back national insurance costs.”