TV licensing spies caught more than 400 people watching without a licence around Hammersmith and Fulham in the first half of this year.
Detector vans cruising Fulham, West Kensington, Hammersmith and Shepherd's Bush picked out 430 offenders between January and June – far more than the 78 caught in neighbouring Kensington and Chelsea, but only one third of the 1,365 brought to book in Ealing.
Patterns of evaders vary, according to the authority, depending on various factors such as the areas monitored by officers at any one time.
Around 95 per cent of homes around the country are correctly licensed.
Ian Fannon, spokesman for TV Licensing, said: "The vast majority of people in Hammersmith and Fulham pay their licence fee, and to be fair to those who pay, we have to be firm with those who attempt to get away without paying.
"We take TV licence evasion very seriously and, while we give people every opportunity to pay, we will not hesitate to prosecute if people continue to break the law.
"We do understand that some people may find it difficult to pay their licence fee in one go, which is why we offer numerous ways to spread the cost, including monthly direct debit, which can be set up very quickly online, and a weekly cash payment plan."
A colour TV licence costs £145.50 and is needed by anyone watching or recording programmes through their TV, computer or any other equipment. Those caught watching illegally can be fined up to £1,000.
