Hillingdon Council spent nearly £8,500 on social media advertising last year, new figures show.
The council spent £8,435.54 advertising on its Facebook page in the 2013/14 financial year.
The figure was up 71% on the previous year, when the council spent £4,940.63 on click-through advertisements linking back to its own website.
So far this financial year, the local authority has spent £6,389.07 on social media advertising.
Mr Duffin said: “Our previous investigations revealed that Hillingdon Council spent nearly £100,000 on their promotional magazine, Hillingdon People, in 2013. Now we see that they are topping this up with additional spend in online advertising.
"Meanwhile, they have cut front-line policing numbers and the maintenance teams who look after our social housing. Is this a proper use of local taxpayers' money?
“UKIP would axe the Hillingdon People magazine and redirect this cash into front line services, such as extra police officers, street cleaning and the NHS, whilst encouraging more interaction by local councillors with their constituents and engagement with local media outlets to get information out.”
'Putting residents first'
Council leader Councillor Ray Puddifoot hit out at the anti-European Union party, saying Mr Duffin's statement showed a lack of understanding of how local authorities operate.
In London, fire, police and public transport services are provided by the Greater London Authority, while local NHS budgets are dictated by central government.
Mr Puddifoot said: "Clearly UKIP have no idea of what is required to run a financially-efficient council.
“Firstly, we are not responsible for the NHS and police budgets, and secondly we have reduced the cost of running the council by £80m since 2010.
“I am afraid that I could not even give them one out of ten for financial ability."
In 2013/14, the council, which recently approved its budget for 2015/16, spent £91,723 publishing its magazine, Hillingdon People, which it prints six times a year.
Last year, Kris Hopkins, local government minister at the time, sent the council a warning letter, saying council magazines should not be published more than quarterly, which the council defied.
Mr Puddifoot said: "The Conservative administration are committed and delighted to be able to keep residents informed about what is going on in the borough, which we regard as part of 'putting residents first'.
“I can, however, understand that with the mess that we would be in with either Labour or UKIP in charge, this would be something that they would not want to share with residents.
“They simply do not understand that keeping residents in the dark is bad policy, or that the cost of doing so is not a problem for the Conservative administration, although again I appreciate that it would be for them."