More people are complaining about claims by pubs, cafés and restaurants in Brighton and Hove that they serve locally sourced food.
But when trading standards officers carried out spot checks on 35 premises, only one could not prove its claims.
Brighton and Hove City Council said that the investigation was carried out in August as part of a national survey.
Officers visited businesses chosen at random and checked paperwork to make sure that claims made about local produce were accurate.
The visits followed a survey carried out earlier this year by trading standards officers in Lancashire.
They found that 32 of 41 randomly selected premises across the county were making misleading claims about the food that they served.
Councillor Mary Mears, the leader of Brighton and Hove City Council, said: “It’s good to see our local food outlets coming out well in the random survey.
“Residents are becoming more interested in where their food comes from.
“The impact of food miles on the environment and a desire to support local businesses are both increasingly important factors for consumers when choosing what and where to eat.”
The council said that there was no absolute definition of what constitutes “local” in relation to food products.
In Brighton and Hove, the criterion used was that food should be sourced either within a 50-mile radius of Brighton and Hove or Sussex or the South Downs.
