Kingston has about 30 fewer police officers than it did four years ago, new figures show.
The Metropolitan Police's latest crime figures and associated data show that staffing levels in the borough have dropped from a high of 329 officers in March 2010 to 299 in January 2014.
But that is still more than Kingston had a year ago, when just 281 officers were working full time in the borough.
The stats represent full-time equivalent figures, taking account of part time working and job sharing, and do not represent an exact headcount.
However, Labour London Assembly member Murad Qureshi said the data still showed mayor Boris Johnson had failed to live up to his promise to increase police numbers.
Mr Qureshi said: "“Despite promising us there would be one thousand more police officers in London, the truth is the mayor has failed to deliver.
"We have lost over 3,000 police officers in London.
"The Mayor has already admitted that there may be flaws in his new community policing plan; the [police inspectorate] HMIC has reported that the Met now has the third lowest visibility of officers in the country.
"The Mayor needs to act on his promise and get officers into our neighbourhoods.”